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Solve by graphing {(3x+4y=-8) (-x+y=5)} I already know the answer I just need the step-by-step equation.

1 Answer

6 votes

Answer: (-4, 1)

Explanation:

To solve graphically, change each equation into slope-intercept form

(y = mx + b)

3x + 4y = -8

+8 +8

3x + 4y + 8 = 0

-4y -4y

3x + 8 = -4y

Divide both sides by -4 to get y by itself

-3/4x - 2 = y or y = -3/4x - 2


Do the same for the other equation.

-x + y = 5

+x +x

y = 5 + x or y = x + 5


Plug in the equations graphically. The point at which the two lines intercept is your answer.

User Bibscy
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