Question

Solve the system using elimination
3x + 3y = –9
3x – 3y = 21
a. (3, –6) b. (–5, 2) c. (3, 3) d. (2, –5)

Answer 1

y=-3-x

3x+9+3x=21
6x=12
x=2

6+3y=-9
3y=-15
y=-5

Answer 2

so the answer is d.

Answer 3

d. (2, –5)

Subtract:
-> -6y = 30
=> y = - 30/6 = -5
=> x = 7 + y = 2