Question

Henrique began to solve a system of linear equations using the linear combination method. his work is shown below

1. 3 (4x-7y=28) -> 12x-21y=84
-2 (6x-5y=31) -> -12x 10y =62

2. 12x-12y=84
-12x 10y =-62
-----------------------
-11y=22

3. y= -2

complete the steps used to solve a system of linear equations by substituting the value of y into one of the original equation s to find the value of x. what is the solution to the system

Answer 1

3.5, -2

Explanation:

Answer 2

3(4x - 7y = 28)
-2(6x - 5y = 31)

12x - 21y = 84
-12x + 10y = -62
0 - 11 y = 22

y = 22/-11
y = -2

12x - 21y = 84
12x - 21(-2) = 84
12x + 42 = 84
12x = 84 - 42
12x = 42
x = 42/12
x = 3.5