Question

Find the missing number so that the equation has infinitely many solutions.

– x + 20 + blank x = – 4 x + 20

Answer 1

-3

Explanation:

To make the equation have infinitely many solutions, we need to make both sides equal.

i will use variable y in place of blank

-x + 20 + yx = -4x + 20

-x + yx = -4x

yx = -3x

y = -3

now we can check the answer

-x + 20 - 3x = -4x + 20

-4x + 20 = -4x + 20

0 = 0

this means there are infinitely many solutions