Question 865016
Solve the system of equations by substitution:
3x - y = 4 (Equation 1)
x + 5y = -4 (Equation 2)


3x - y = 4

Subtract 3x from each side of the equation.

3x - y - 3x = 4 - 3x

-y = 4 - 3x

Divide each side by -1

y = -4 + 3x (Equation 3)

Substitute Equation 3 into Equation 2.

x + 5y = -4

x + 5(-4 + 3x) = -4

x - 20 + 15x = -4

16x - 20 = -4

16x - 20 + 20 = -4 + 20

16x = 16

x = 1


Substitute x = 1 into Equation 1.


3x - y = 4

3(1) - y = 4

3 - y = 4

3 - y - 3 = 4 - 3

-y = 1

Divide each side by -1

y = -1



Answer:

x = 1

y = -1







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