Explain the solving of the equation 3x+15=0?

10 Answers

udonbutterfly's profile pic

udonbutterfly | Student, College Freshman | (Level 1) Valedictorian

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3x + 15=0 In order to solve for x you are going to subtract 15 both sides.

3x +15 -15=0 -15 The 15 on the left is going to cancel out and leave you with 3x.

3x = -15 Now divide 3 on both sides of the equation

3x/3 = -15/3 You will be left with x by itself on the left side.

x = -5 Here is your answer.

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eli468 | Student, Undergraduate | (Level 1) Valedictorian

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In this equation you are solving for x, therefore you want to try and get x to be all by itself on one side of the equation. In order to do this you must first move the 15 over to the right side. You can manipulate the equation by adding, subtracting, dividing, multiplying, etc. the same number on both sides of the equation. In this case you want to take the 15 away first. In order to do this you have to subtract 15. Since it has to be taken away on both sides it leaves a negative 15 on the right. 


    -15   -15


From here you can still want to isolate x on it's own. In order to that you need to divide x by 3. Therefore you must divide both sides of the equation by 3.

3x/3=x    -15/3=-5


Now x is isolated and the equation is solved giving the answer of x=-5

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ik9744 | Student, Grade 9 | (Level 1) Valedictorian

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3x+15=0 Equation

3x = 0 - 15 Subtract 15 from both sides

3x = -15 0 - 15

x = -5  Answer

zumba96's profile pic

zumba96 | Student, Grade 11 | (Level 3) Valedictorian

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There is a 0 but you need to find x, first isolate x then


Move 15 on the other side


Then divide -15 by 3


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jess1999 | Student, Grade 9 | (Level 1) Valedictorian

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3x + 15 = 0

To solve this equation add 15 on both sides

By adding 15 on both sides, your equation should be

3x = -15 now divide both sides by 3

By dividing both sides by 3, your equation should be

x = -5 which is your answer

Jyotsana's profile pic

Jyotsana | Student, Grade 10 | (Level 1) Valedictorian

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3x+15=0   Subtract 15 on both side


3x=-15     Divide both side by 3



jscorpio43's profile pic

jscorpio43 | Middle School Teacher | (Level 1) eNoter

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minus 15 on both sides

the first set of 15's cancel

then 0-15= -15

3x=-15 divide both sides 3

3x divided by 3=x -15 divided by 3 =-5


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neela | High School Teacher | (Level 3) Valedictorian

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To solve 3x+15 = 0


3x+15 = 0. If we subtract equals from both sides the equation remains same like balance. And the solution of the equation also does not change. Therefore we choose 15 to be subtracted from both sides. This would make 15 vanish from left and only unknown x's remainn on the left.

3x+15 -15 = 0-15. Simplify>

3x = -15. We can divide both sides by equal number. Even then the solution of the equation or the balance of the equation remains same or in equality. We choose 3 as this action of dividing by 3  makes left side 3x reduce to x forwhich we get a value or solution through a numerical value on the right.

3x/3 = -15/3.  Somplify both sides:

x=-5. So x=-5 is the solution to the given equation, 3x+15 = 0.


krishna-agrawala's profile pic

krishna-agrawala | College Teacher | (Level 3) Valedictorian

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Given equation:

3x + 15 = 0

Solving of this equation means finding the value of x. We can do this in following steps.

Transfer the term involving only number on the left side of the equation to the right hand side. Please note that in an equation when we transfer any term from one side to the other, the sign of the term gets changed. Thus, when we transfer 15 from left hand side to the right hand side, it becomes -15. In this way the equation becomes:

3x = -15

Now we divide both side of the equation by 3, so that value of the term on left hand side becomes equal to x. Thus the equation becomes:

3x/3 = -15/3

Simplifying the terms in equation we get:

x = -5


x = -5

giorgiana1976's profile pic

giorgiana1976 | College Teacher | (Level 3) Valedictorian

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In order to solve the linear equation, we'll have to find a value for x so that the equation to hold, even after the substitution of the unknown x with the found value was made.

A proper manner to solve this type of equation would be to subtract, both sides of the equation, the opposite value of the one of the left side, so that, in the end, the left side to contain only the unknown x.

3x+15-15 = 0-15


Now, to move 3 across the equal sign, we need to divide both sides of the equation with 3.

3x/3 = -15/3

x = -5