Question 269623: Barry is helping his friend understand how to solvesystems of equations. He wants to give her a problem to practice. He wants to give her a problem that has two lines that intersect at the point (-3,7). Help him by writing a system of equations that will have (-3,7) as a solution and demonstrate how to solve it.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! writing a system of equations that will have (-3,7) as a solution and demonstrate how to solve it.
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x = -3 and y = 7
3x = -9 and 4y = 28
Add to get the 1st equation:
3x + 4y = 19
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x = -3 and y = 7
-2x = 6 and 2y = 14
Add to get:
-2x + 2y = 20
-x + y = 10
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System:
3x + 4y = 19
-x + y = 10
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Solve by substitution:
y = x + 10
3x + 4(x+10) = 19
7x + 40 = 19
7x = -21
x = -3
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Since y = x+10
y = -3+10 = 7
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solution: x = -3, y = 7
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cheers,
Stan H.
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