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How do I solve system of equations by substitution
y=-2x+2
y=7x+11

User Tfinniga
by
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1 Answer

4 votes

Answer:

(-1, 4)

Explanation:

We are told that:

y = -2x + 2 and

y = 7x + 11.

We can eliminate "y" by setting these two equations = to each other:

-2x + 2 = 7x + 11.

We need to solve this equation for x.

Adding 2x to both sides, we get 2 = 9x + 11.

Subtracting 11 from both sides results in -9 = 9x. Thus, x = -1.

Find y by subbing -1 for x in either of the given equations.

If we use the 2nd equation, then y = 7(-1) + 11, or y = 11-7, or y = 4.

The solution of this system of linear equations is (-1, 4)

User Owenmarshall
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8.1k points