Question

7. Solve 2x - y = 7 for y. Then find the value of y when x = -1,0, and 1.

Answer 1

Explanation:

We want to solve 2x - y = 7 for y. Start by changing the signs of all terms, obtaining -2x + y = -7. Now add 2x to both sides, obtaining y = 2x - 7.

Now evaluate this at x = -1: y(-1) = 2(-1) - 7 = -2 - 7 = -9

Now evaluate this at x = 0: y(0) = 2(0) - 7 = 0 - 7 = -7

Now evaluate this at x = 1: y(1) = 2(1) - 7 = 2 - 7 = -5