CPM Homework Help : CAAC Problem 7-38

7-38.

Hint (a):

Use the Elimination Method.

Step 1(a):

Add the equations together vertically.
The result is: 8x = −8

Step 2(a):

Solve for x by dividing the equation by 8. x = −1

Step 3(a):

Substitute x into one of the original equations to find y. 5(−1) − y = 2

Step 4(a):

Solve for y.
y = −7

Answer (a):

(−1, −7)

Hint (b):

Use the Elimination Method.

Step 1(b):

Multiply the 2nd equation by −2

Steps (b):

Follow the steps outlined in part (a).

Hint (c):

Try rewriting the 2nd equation. What do you notice?