Question

Use the elimination method to solve the system for x and y.
16x+7y=25
4+8x-2y=0
Select one:
a. (3, 1/4)
b. (1/4, -3)
c. (-1/4, -3)
d. (1/4, 3)

Answer 1

1: 16x+7y=25 (multiply by 2) you get: 32x+14y=50

2: 4+8x-2y=0 (rearranging you get 8x-2y=-4)
multiply by 7: you get 56x-14y=-28

now add the 1 and 2, you get:

32x+14y=50
+ 56x-14y=-28
_________________
88x=22
x=22/88
x=1/4

substitute into x=1/4 into 1:
16(1/4)+7y=25
4+7y=25
7y=25-4
7y=21
y=21/7
y=3

Therefore answer is d. (1/4,3)

Answer 2

thanks(: