Solve the system by the

substitution method.

Sol

of

x + 7y = - 1

- 4x - 2y = - 22

First make x stand alone: x = - 7y-1

Substitute this to where you find the letter x in the second equation

-4 (-7y-1) - 2y=-22

Multiply the - 4 by the numbers in the parentheses and son't forget your signs

28y+4-2y=-22

26y=-22-4

26y=26

Divide both sides by 26

y = - 1

Substitute - 1 in the 3 equation to find x

X = - 7y-1

=-7 (-1) - 1

=7-1

X = 6

(6, - 1)

Step-by-step explanation:

Given the 2 equations

x + 7y = - 1 → (1)

- 4x - 2y = - 22 → (2)

Rearrange (1) expressing x in terms of y by subtracting 7y from both sides

x = - 1 - 7y → (3)

Substitute x = - 1 - 7y into (2)

- 4 ( - 1 - 7y) - 2y = - 22 ← distribute and simplify left side

4 + 28y - 2y = - 22

4 + 26y = - 22 (subtract 4 from both sides)

26y = - 26 (divide both sides by 26)

y = - 1

Substitute y = - 1 into (3) for corresponding value of x

x = - 1 - 7 ( - 1) = - 1 + 7 = 6

Solution is (6, - 1)