Question

When x=7, what is the value of y for the equation x-2y=8?

Answer 1

-0.5

Explanation:

7 - ? = 8

or

8 + ? = 7

since 7 < 8 we know the answer is negative, so instead we could write:

8 - ? = 7

by using mental math we know that the answer is 1, so:

8 - 1 = 7

7 - -1 = 8

(tip a double negative equals a positive so instead rewrite the equation as addition; 7 + 1 = 8)

Now we must remember that -1 = 2y so to solve for y we must divide each side by 2. -1/2 = 0.5 and 2y/2 = y so -0.5 = y. Have a great day! Hope this helps and GOOD LUCK!!!!!!!

Answer 2

7-2y=8

-2y=8-7

-2y=1

y=1/-2