Y= -4x + 15 y = 4x - 41 substitution

Substitute y = -4x + 15 to the equation y = 4x - 41:

-4x + 15 = 4x - 41        subtract 15 from both sides

-4x = 4x - 56       subtract 4x from both sides

-8x = -56       divide both sides by (-8)

x = 7

Put the value of x to the first equation:

y = -4(7) + 15

y = -28 + 15

y = -13