Question

Solve the system of equations given

5x+2y=9
2x-3y=15

A. (3,-3)
B. (-3,12)
C. (12,-3)
D. (-3,3)

Answer 1

A) 5x+2y=9

B) 2x-3y=15

Multiply A) by 1.5

A) 7.5x +3y = 13.5 then add it to B)

B) 2x-3y=15

9.5x = 28.5

x = 3

5*3 + 2y=9

2y = -6

y = -3

answer is A

Explanation:

Answer 2

{x = 3 , y = -3 thus the answer is A

Explanation:

Solve the following system:

{5 x + 2 y = 9 | (equation 1)

{2 x - 3 y = 15 | (equation 2)

Subtract 2/5 × (equation 1) from equation 2:

{5 x + 2 y = 9 | (equation 1)

{0 x - (19 y)/5 = 57/5 | (equation 2)

Multiply equation 2 by 5/19:

{5 x + 2 y = 9 | (equation 1)

{0 x - y = 3 | (equation 2)

Multiply equation 2 by -1:

{5 x + 2 y = 9 | (equation 1)

{0 x+y = -3 | (equation 2)

Subtract 2 × (equation 2) from equation 1:

{5 x+0 y = 15 | (equation 1)

{0 x+y = -3 | (equation 2)

Divide equation 1 by 5:

{x+0 y = 3 | (equation 1)

{0 x+y = -3 | (equation 2)

Collect results:

Answer: {x = 3 , y = -3