Question

Please help!

For the following system,

3x + y = 8
−x − 2y = −10

if you isolated x in the second equation to use the substitution method, what expression would you substitute into the first equation?
−2y + 10
2y + 10
2y − 10
−2y − 10

Answer 1

-2y+10

Explanation:

-x - 2y = -10

add 2y to both sides

-x = -10 + 2y OR 2y - 10

divide both sides by -1

x = -2y+10