Answer: A
One solution x = 60/23 y=12/23 z= -72/23
How? in the photos attached
Explanation:
Take the first equation and rewrite
5x +y = 1 becomes y = 1 -5x
Substitute for y in the second equation
Solve for x
The rest of the steps are more of the same: substitute and solve as scownin the photos
They overlap a bit to be sure it's all there