Question

Solve the system of linear equations using elimination.

10x + 10y = −10
9x + 10y = −18
A) (8, 9)
B) (8, −9)
C) (−8, 9)
D) (−8, −9)

Answer 1

B

Explanation:

Answer 2

(x , y) = (8, -9)

Explanation:

We have the equations as,

10x + 10y = -10 -------------------------(1)

and

9x + 10y = -18 ---------------------------(2)

Now deducting (2) from (1) we get,

x = 8 ----------------------(3)

Putting the value of x from (3) in (1) we get,

10y = -90

⇒y = -9 --------------------(4)

So, from (3) and (4) we get that,

(x , y) = (8, -9) (Answer)