PLEASE CAN SOMEONE HELP!!!????

Use elimination to solve for x and y:

−2x−y=9

2x−9y=1

My Choices are....

a. (−4,−1)
b. (−1,−4)
c. (5,1)
d. (−1,−7)

Respuesta :

add them 2 equations to eliminate x's

-2x-y=9
2x-9y=1 +
0x-10y=10

-10y=10
divide by -10
y=-1

sub back

-2x-y=9
-2x-(-1)=9
-2x+1=9
-2x=8
divide by -2
x=-4

y=-1

(x,y)
(-4,-1)


A