Question

Which of the following equations is equivalent to x - y = 8?

1) 2x - 4y = 8
2) 2x - 4y = 64
3) 4x - 2y = 64

Answer 1

Say x = 12 and y = 4
12 - 4 = 8

Number 1
2(12) - 4(4) = 8
24 - 16 = 8
Number 1 is your Answer

Answer 2

The equivalent equation is 1) 2x - 4y = 8

Explanation:

The given equation is x - y = 8.

Here we have 8 on the right hand side.

Now find the equation which has 8 on the right hand side.

It is 2x - 4y = 8

Therefore, the equivalent equation is 1) 2x - 4y = 8

Now let's find the value of x and y.

From the equation x - y = 8, we get

x = y + 8

Now plug in x = y + 8 in the equation 2x - 4y = 8

2(y + 8) -4y = 8

Use the distributive property

2y + 16 -4y = 8

-2y + 16 = 8

-2y = 8 -16

-2y = -8

Dividing both sides by -2, we get

y = 4

Now plug in y = 4 in x = y + 8 to get the value of x.

x = 4 + 8 = 12

So the value of x = 12 and y = 4

If we plug these values in the above two equations, we get will get 8.