Question

520 + 40x = 3800 - 120y

Answer 1

Solve for which variable?

Answer 2

x

Answer 3

520 + 40x = 3800 - 120y
40x = 3800 - 520 - 120y
40x = 3280 - 120y
x = (3280 - 120y)/40

Answer 4

so what is x?

Answer 5

like when i plug it in, it's going to work

Answer 6

x = 82 - 3 y

Answer 7

what is it exactly? lol

Answer 8

Simplifying
520 + 40x = 3800 + -120y

Solving
520 + 40x = 3800 + -120y

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-520' to each side of the equation.
520 + -520 + 40x = 3800 + -520 + -120y

Combine like terms: 520 + -520 = 0
0 + 40x = 3800 + -520 + -120y
40x = 3800 + -520 + -120y

Combine like terms: 3800 + -520 = 3280
40x = 3280 + -120y

Divide each side by '40'.
x = 82 + -3y

Simplifying
x = 82 + -3y
so
plug x in
Simplifying
520 + 40(82 + -3y) = 3800 + -120y
520 + (82 * 40 + -3y * 40) = 3800 + -120y
520 + (3280 + -120y) = 3800 + -120y

Combine like terms: 520 + 3280 = 3800
3800 + -120y = 3800 + -120y

Add '-3800' to each side of the equation.
3800 + -3800 + -120y = 3800 + -3800 + -120y

Combine like terms: 3800 + -3800 = 0
0 + -120y = 3800 + -3800 + -120y
-120y = 3800 + -3800 + -120y

Combine like terms: 3800 + -3800 = 0
-120y = 0 + -120y
-120y = -120y

Add '120y' to each side of the equation.
-120y + 120y = -120y + 120y

Combine like terms: -120y + 120y = 0
0 = -120y + 120y

Combine like terms: -120y + 120y = 0
0 = 0

Solving
0 = 0
This equation is an identity, all real numbers are solutions.