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Solve the system of equation by substitution. y=10x+2-5x+4y=-27

User Krishnam
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System of Equations

Solve the system

y = 10x + 2

-5x + 4y = -27

By substitution.

The method of substitution requires we solve for one of the variables and substitute its expression into the other equation.

The first equation has already isolated the variable y. We substitute it in the second equation as follows:

-5x + 4(10x + 2) = -27

Operating:

-5x + 40x + 8 = -27

Simplifying:

35x + 8 = -27

Subtracting 8:

35x = -27 - 8

35x = -35

Dividing by 35:

x = -35/35

x = -1

Now substitute in the first equation:

y = 10*(-1) + 2

y = -10 + 2

y = -8

Solution: x=-1, y=-8

User Sandwood
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