# Math Homework Help

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• Math
L(t) = 1208 ( 1.265)^t The environmentalists needs t years in order to solve the problem. Since they have enough rainbow for only 10,000 leprechauns, then they have time until the population reach...

Asked by mamawhit on via web

• Math
Given that: v1= 226 where D= 6 in ==> The radius (r1)= 6/2 = 3 ==> v1 = r^2 * pi * h1 ==> 226 = 9 * pi * h1...........(1) We need to find the value of the volume (v2) when the height is...

Asked by b198125 on via web

• Math
To cover a certain area the builder needs x numbers of 4-in tiles and y numbers of 16-in tiles. If he will only use the 4-in tiles he will need to replace y numbers of 16-in tiles with the 4-in...

Asked by ifrab on via web

• Math
In the problem we are given the length of two of the sides of the triangle and we have two of the angles. The sum of the three angles of a triangle is equal to 180 degrees. Using this, the third...

Asked by jatmeh on via web

• Math
The general form of a circle with a center (a, b) and radius r is (x - a)^2 + (y - b)^2 = r^2 We have the center as (-2 , -3) and the radius is 8 Substituting these values we get : (x + 2)^2 + ( y...

Asked by mia2011 on via web

• Math
We have to find the units digit of 3^4027. 3^1 = 3, 3^2 = 9, 3^3 = 27, 3^4 = 81, 3^5 = 243... We see that the units digit follows the series 3, 9, 7, 1 and it repeats after 4 powers. 3^4027 =...

Asked by sylli on via web

• Math
If the given integration is correct the derivative of (u/8)*(2u^2 - a^2)sqrt( a^2 - u^2) + (a^4/8)arc sin (u/a) + C should be u^2*sqrt ( a^2 - u^2) [(u/8)*(2u^2 - a^2)sqrt( a^2 - u^2) + (a^4/8)arc...

Asked by tgl223 on via web

• Math
We have to find the tangent to the circle x^2 + y^2 + 10x - 6y - 2 = 0 parallel to y = 2x without using calculus. The given circle is x^2+y^2+10x-6y-2=0 => x^2+ 10x + 25 + y^2 - 6y + 9 = + 25 +...

Asked by fish-swim on via web

• Math
The line x + 8y = 9 can be rewritten in the form y = -x / 8 + 9/8 where -1/8 is the slope. The angle that is formed by the line with the positive x – axis is arc tan (-1/8). We need to find the...

Asked by beatrice0866 on via web

• Math
The slope of the tangent to a curve at any point is the value of the first derivative at that point. Here, we have the curve y = sqrt ( 2x^2 +1) y' = 4x * (1/2) (2x^2 + 1)^(-1/2) => y' = 2x/...

Asked by littlecrumpet on via web

• Math
The area of a triangle is given by the formula (1/2)* base * height. To enclose a triangle with the largest area within a rectangle its base would have to be one of the sides of the rectangle and...

Asked by schooldump on via web

• Math
Imagine 4-inch tiles laid out on top of a 16-inch square tile. There would be 4 rows of 4-inch squares, with 4 tiles in each row. Each 4-inch square tile has an area of 16 square inches (4 x 4),...

Asked by s-oh-nine on via web

• Math
I think by x you mean one of the angles of the triangle. If we look at the relation y = sin x , the independent variable is x and the dependent variable is y. The value of sin x for an angle x is...

Asked by kwaldrop on via web

• Math
You have the answer with you, it's the formula, you just need to substitute the numbers. I'll help you with that. Bob has invested \$1000 in the bank CD, so P = \$1000 The CD earns 3% interest...

Asked by sammysoso on via web

• Math
We have to simplify: (x^2-8x+16)/(x^2-x-12)÷(4x-x^2)/(2x) Now, x^2 - 8x + 16 = (x - 4)^2 x^2 - x - 12 = x^2 - 4x + 3x - 12 => x(x - 4) + 3(x - 4) = (x + 3)(x - 4) 4x - x^2 = x(4 - x)...

Asked by swavers on via web

• Math
The replicas in Katy of the Forbidden Garden terracotta army are 1/3 scale. So a replica is 1/3 the dimensions of the original. The replica in Katy has a height of 22 inches. If the original has a...

Asked by b198125 on via web

• Math
We have to solve the following set of simultaneous equations: x - 2y = 6 ...(1) x + 2y = 8 ...(2) (2) - (1) => x + 2y - x + 2y = 8 - 6 => 4y = 2 => y = 2/4 => y = 1/2 substitute in (1)...

Asked by torrip996 on via web

• Math
We have to solve the following set of simultaneous equations: 2x + 4y = 1 ...(1) 4x + 9y = 2 ...(2) 2*(1) - (2) => 4x + 8y - 4x - 18y = 2 - 2 => -10y = 0 => y = 0 substitute in (2) 4x + 0...

Asked by timw996 on via web

• Math
We have to solve the following set of simultaneous equations: 3x + 2y = 6 ...(1) 18x + y = 9 ...(2) 6*(1) - (2) => 18x + 12y - 18x - y = 36 - 9 => 11y = 27 => y = 27/11 substitute in (2)...

Asked by thomas666 on via web

• Math
We have to prove that the functions f(x) = sqrt (x^2 + 5) and g(x) = (2*sqrt x – 1)^2 grow at the same rate as x -->inf. Two functions grow at the same rate if [lim x--> inf ( f(x) )] /...

Asked by carolinesmiths on via web

• Math
We have to find the derivative of f(x) = 5x * (x-1)^4 We can use the product rule here: f(x) = 5x * (x-1)^4 f'(x) = (5x)' * (x-1)^4 + 5x * [(x-1)^4]' => f'(x) = 5* ( x - 1)^4 + 5x * 4*(x - 1)^3...

• Math
We know that the derivative of ln x = 1/x , but ln x is log(e) x. We have to find the derivative of log(10) (x^3 + 3x). First we convert it to log to the base e. y = log(10) (x^3 + 3x) => y =...

Asked by xetaalpha2 on via web

• Math
We have to determine the value of Int [ (sin x)^3 dx] Int [ (sin x)^3 dx] => Int [ (sin x)^2* sin x dx] => Int [ (1 – (cos x)^2 )* sin x dx] let u = cos x => du = -sin x dx => Int [...

Asked by xetaalpha on via web

• Math
We have to find the integral of ln x. The easiest way to do this is by using integration by parts. The formula we have to substitute values in is Int [ u dv] = u*v – Int [ v du] …(1) Take u =...

Asked by xetabeta on via web

• Math
We have to solve (x+1)^2=2x^2-5x+11 for x. (x+1)^2=2x^2-5x+11 open the brackets => x^2 + 2x + 1 = 2x^2 - 5x + 11 => x^2 - 7x + 10 = 0 => x^2 - 5x - 2x + 10 = 0 => x(x - 5) - 2(x - 5) =...

Asked by stsf on via web

• Math
The model that Ariana and her father build has a scale of 0.08. Each foot in the real structure is represented as 0.08 foot in the model. The square footage of the model is 7.68 and one side is 3.2...

Asked by ifrab on via web

• Math
To find the value of the given expression: 2048x^67 * 9850xy, multiply the numeric terms and the terms x and y. 2048*x^67 * 9850*x*y => 2048*9850 * x*67*x * y => 20172800 * x^(67 + 1) * y...

Asked by luisdc13 on via web

• Math
The pilot is travelling at an airspeed of 100 km/h towards the East. The pilot has to steer the airplane to tackle the wind which is blowing. The wind is blowing at 100 km/h at an angle of 25...

Asked by rosemin on via web

• Math
If the roots of the equation are equal, since the equation is a quadratic, its discriminant has to be zero. Discriminant = delta = b^2 - 4ac a,b,c, are the coefficients of the equation: delta =...

Asked by ishro on via web

• Math
Let the total number of camels be C. We have that (1/4) of the camels had been seen in the forest. Twice the square root of the total number had gone to the forest. The number that remains is equal...

Asked by kanug on via web

• Math
We have to determine (4* sqrt 2 - 2 sqrt 3) (4* sqrt 2 + 2* sqrt 3) (4* sqrt 2 - 2 sqrt 3) (4* sqrt 2 + 2* sqrt 3) => 16* 2 + 8*sqrt 3* sqrt 2 - 8*sqrt 2* sqrt 3 - 4*3 => 32 - 12 => 20 The...

Asked by narutoclan25 on via web

• Math
We have to determine (2* sqrt 5 + 3*sqrt 3)^2 (2* sqrt 5 + 3*sqrt 3)^2 => (2* sqrt 5)^2 + (3*sqrt 3)^2 + 2* 2* sqrt 5*3* sqrt 3 => 4*5 + 9*3 + 12* sqrt 15 => 20 + 27 + 12*sqrt 15 => 47...

Asked by chaozjapan1 on via web

• Math
We have to simplify sqrt 98 + sqrt 32 - sqrt 63 sqrt 98 + sqrt 32 - sqrt 63 => sqrt 49*2 + sqrt 16*2 - sqrt 9*7 => 7* sqrt 2 + 4* sqrt 2 - 3*sqrt 7 => 11* sqrt 2 - 3* sqrt 7 The required...

Asked by tame25 on via web

• Math
Given that log 4 (x) = 12 We need to find the values of log2 (x/4) Let us use the logarithm properties to simplify. We know that log a/b = log a - log b ==> log2 (x/4) = log2 x - log2 4 But log2...

Asked by genieee on via web

• Math
Let the sides be x, y and the hypotenuse h. Given that h is 2 more than the longer sides. Let the longer side be x. ==> h = x+2...............(1) The shorter side (y) is 7 less than the longer...

• Math
Let the numbers be x and y. Given that the sum is 20. ==> x + y= 20 ..............(1) Also, given that the larger number is 4 less than twice the smaller. ==> x = 2y -4 ..............(2) We...

Asked by alinnne on via web

• Math
Given that the area of the rectangle is 15 cm^2. Also, given that the perimeter is 16 cm^2 We need to find the length of the sides. ==> Let the sides be L and w. ==> L*W = 15 ...........(1)...

Asked by neefo on via web

• Math
Let the side of the second square be s, the size of the first is 5 less than the second or s - 5. The area of the larger square is s^2. This is four times the area of the smaller square which is (s...

Asked by jojoogel on via web

• Math
Let us assume that the numbers are x and y. Given that the sum of the numbers is 26. ==> x+ y= 26............(1) Also, given that the product is 165. ==> x*y = 165..........(2) We will use...

• Math
Let the revenue be R, the profit be P, and the cost be C. Then, we know that: Profit = Revenue - cost ==> Given that R= x^2+100x Also, given that C = 240x+500 ==> P = x^2 +100x - 240x -500...

Asked by rogeryyo on via web

• Math
Let f(x) = (x+3)/(2x-5) We will use the quotient rule to find the derivative. We will assume that f(x) = u/v such that: u= x+3 ==> u' = 1 v = 2x-5 ==> v' = 2 ==> Then, we know that...

Asked by meterya on via web

• Math
The length of a rectangular garden is 2 feet longer than 3 times its width. The perimeter of the garden is 100 feet. We have to find the width and the length of the garden. The perimeter of a...

Asked by roooze on via web

• Math
The circumference of a circle with a radius equal to r is given by the expression 2*pi*r. Here, we are given the circumference and have to find the radius. Let the radius be r 2*pi*r = 72*pi =>...

Asked by zaidzoo on via web

• Math
We can solve y=(2+4x^2)^3 in two ways. One is use the chain rule y=(2+4x^2)^3 y' = 3*8x*(2 + 4x^2)^2 => y' = 24x*( 4 + 16x^4 + 16x^2) => y' = 96x + 384x^5 + 384x^3 Else expand (2+4x^2)^3...

Asked by catbyshe on via web

• Math
We have to simplify (x^2-y^2+2x+1)/[(x+y)^2+2(x+y)+1] (x^2-y^2+2x+1)/[(x+y)^2+2(x+y)+1] => (x^2-y^2+2x+1)/(x + y + 1)^2 => (x^2 +2x+1 - y^2)/(x + y + 1)^2 => [(x + 1)^2 - y^2]/(x + y +...

Asked by landishigh on via web

• Math
The point (2 , 3) lies on the graph f(x) and g(x). So we have 3 = a*2 + b - 9 and 3 = 2*b*2 - a This gives us two equations to solve for a and b. 2a + b = 12...(1) 4b - a = 3 ...(2) 4b - a = 3...

Asked by afrokaa on via web

• Math
We have to determine the result of the difference of fractions. This can be done by equating the denominator in both the fractions and subtracting the terms in the numerator. If possible the final...

Asked by xetabeta on via web

• Math
We have to find the area of the triangle with sides 8, 15, 17 without using Heron’s formula. If we have a look at the sides, see that 8^2 = 64, 15^2 = 225 and 17^2 = 289. Now, 64 + 225 = 289...

Asked by thomas666 on via web

• Math
We have to find lim x--> inf, [1/(x - sqrt(x^2 + 2x))]. [1/(x - sqrt(x^2 + 2x))] => (x + sqrt(x^2 + 2x)/ (x - sqrt(x^2 + 2x)* (x + sqrt(x^2 + 2x) => (x + sqrt(x^2 + 2x)/ x^2 - x^2 - 2x...

Asked by xetaalpha2 on via web