Question

2y + 4x = 18
2y - 3x = 4
A. (6, -3)
B. (2, 5)
C. (5, -1)
D. (3, 3)

Answer 1

Solve the following system:
{4 x+2 y = 18 | (equation 1)
2 y-3 x = 4 | (equation 2)
Add 3/4 × (equation 1) to equation 2:
{4 x+2 y = 18 | (equation 1)
0 x+(7 y)/2 = 35/2 | (equation 2)
Divide equation 1 by 2:
{2 x+y = 9 | (equation 1)
0 x+(7 y)/2 = 35/2 | (equation 2)
Multiply equation 2 by 2/7:
{2 x+y = 9 | (equation 1)
0 x+y = 5 | (equation 2)
Subtract equation 2 from equation 1:
{2 x+0 y = 4 | (equation 1)
0 x+y = 5 | (equation 2)
Divide equation 1 by 2:
{x+0 y = 2 | (equation 1)
0 x+y = 5 | (equation 2)
Collect results:
Answer: |
| {x = 2
y = 5

Answer 2

B?

Answer 3

Mhm ^-^

Answer 4

thanks