Solve the equations 4x - 2y = 8, 2x - y = 3.

3 Answers | Add Yours

justaguide's profile pic

justaguide | College Teacher | (Level 2) Distinguished Educator

Posted on

The set of equations 4x - 2y = 8 and 2x - y = 3 has to be solved.

Each of these equations represents a line in the x-y plane. It is possible to write each of them in the slope-intercept form, y = m*x + b.

4x - 2y = 8

=> y = 2x - 4

2x - y = 3

=> y = 2x - 3

For both these equations, the slope is the same. These equations represent parallel lines and lines that are parallel to each other do not intersect. As a result, the given set of equations does not have a solution.

jess1999's profile pic

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

Posted on

4x - 2y = 8

2x - y = 3 

To solve these two equations , first multiply everything in the second equation by 2 

By multiplying everything in the second equation by 2 , you should get 

2x - 2y = 8

4x - 2y = 6  now subtract the two equations 

By subtracting the two equations , you should get 

-2x = 2 now divide both sides by -2 

By dividing both sides by -2 , you should get 

x = -1 which is your answer for " x " 

Now that we have the answer for " x " , we should plug -1 into one of the equation . Let's plug it into 2x - y = 3 

By plugging -1 into the equation we should get 

2 ( -1 ) - y = 3 multiply 2 with -1 

By multiplying , you should get 

-2 - y = 3 now plus 2 on both sides 

By adding 2 on both sides , you should get 

-y = 5 now divide both sides by -1 

By dividing both sides by -1 , you should get 

y = -5 which is your answer for  " y " 

So your answer is , ( -1 , -5 )

atyourservice's profile pic

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

Posted on

4x - 2y = 8,

I am going to try to get x alone first:

subtract 4x

-2y = 8 - 4x

divide by -2:

y = -4 + 2x

now plug in this solution as Y in order to solve for x

2x - y = 3

2x - (-4+2x) = 3

2x + 4 - 2x = 3

move like terms to the same side:

2x - 2x = 3-4

0=-1

this problem does not have solutions, you can tell because 0 does not equal 1, there is nothing you can multiply 0 by in order to get 1 . 

We’ve answered 318,914 questions. We can answer yours, too.

Ask a question