Question

5) 5x+y=9 10x - 7y=-18

Answer 1

Answer:

x = 1 , y = 4

Step-by-step explanation:

Solve the following system:

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

10 x - 7 y = -18 | (equation 2)

Swap equation 1 with equation 2:

{10 x - 7 y = -18 | (equation 1)

5 x + y = 9 | (equation 2)

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

{10 x - 7 y = -18 | (equation 1)

0 x+(9 y)/2 = 18 | (equation 2)

Multiply equation 2 by 2/9:

{10 x - 7 y = -18 | (equation 1)

0 x+y = 4 | (equation 2)

Add 7 × (equation 2) to equation 1:

{10 x+0 y = 10 | (equation 1)

0 x+y = 4 | (equation 2)

Divide equation 1 by 10:

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

0 x+y = 4 | (equation 2)

Collect results:

Answer: {x = 1 , y = 4