can someone please help me answer this question?

Solve the system using elimination.
2x +6y = -12
5x - 5y =10

a. (2,1)
b. (0,-2)
c. (-2,0)
d. (1,2)

Question

can someone please help me answer this question?

Solve the system using elimination.
2x +6y = -12
5x - 5y =10

a. (2,1)
b. (0,-2)
c. (-2,0)
d. (1,2)

anonymous · Answer

Choose one of the variable to eliminate let's go with 'x'
We need to make the x terms in each equation so that when we add them they cancel.

The LCD of 2 and 5 is 10. 
2x+6y=-12 multiply by (-5)
5x-5y=10 multiply by (2)

(-10x-30y = 60)  (eqn 3)
+(10x-10y=20 )   (eqn 4)

Add equation 3 to equation 4 above you get
-40y = 80
solve for y: y=-2

Go back to the original equations: choose equation (1)or (2) and substitute y=-2
2x+6(-2)=-12
solve for x = 0

Therefore, your answer as an ordered pair is (0,-2) which corresponds to b.

anonymous · Answer

Do you have any questions on what I did?