Use substitution to solve the system of equations

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Shelly J. | Excellent Maths Tutoring for academic successExcellent Maths Tutoring for academic su...

x=2y+7 equation 1

x=y+4

y=x-4 equation 2

substitute the value of y in equation 1

x=2(x-4)+7

x=2x-8+7

x=2x-1

x=1

substitute the value of x in equation 2

y=1-4

y=-3

Substitute x from first equation into second

2y + 7 = y + 4

y = 4 - 7 = -3

Substitute value of y into first equation

x = 2(-3) + 7

x = -6 + 7 = 1

:)

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