Question

Solve the system of linear equations using elimination. −7x + 3y = −6 −3x + 3y = 6

Answer 1

(3, 5)

Explanation:

−7x + 3y = −6

−3x + 3y = 6

Subtract the second equation from the first.

−4x = −12

x = 3

Then substitute. → −7x + 3y = −6 → −7(3) + 3y = −6

y = 5

Answer 2

x = 3 , y = 5

Explanation:

Solve the following system:

{3 y - 7 x = -6 | (equation 1)

3 y - 3 x = 6 | (equation 2)

Subtract 3/7 × (equation 1) from equation 2:

{-(7 x) + 3 y = -6 | (equation 1)

0 x+(12 y)/7 = 60/7 | (equation 2)

Multiply equation 2 by 7/12:

{-(7 x) + 3 y = -6 | (equation 1)

0 x+y = 5 | (equation 2)

Subtract 3 × (equation 2) from equation 1:

{-(7 x)+0 y = -21 | (equation 1)

0 x+y = 5 | (equation 2)

Divide equation 1 by -7:

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

0 x+y = 5 | (equation 2)

Collect results:

Answer: {x = 3 , y = 5