SOLUTION: solve by substitution: 4x-y=7 2x-5y=-1

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Question 452230: solve by substitution:
4x-y=7
2x-5y=-1
Answer by algebrahouse.com(1659) About Me  (Show Source):
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4x - y = 7------> -y = -4x + 7------- y = 4x - 7
2x - 5y = -1

2x - 5y = -1 {bottom equation}
2x - 5(4x - 7) = -1 {substituted 4x - 7, in for y, into bottom equation}
2x - 20x + 35 = -1 {used distributive property}
-18x = -36 {subtracted 35 from both sides}
x = 2 {divided both sides by -18}

y = 4x - 7
y = 4(2) - 7 {substituted 2, in for y, into 4x - 7}
y = 8 - 7 {multiplied}
y = 1 {subtracted}

x = 2 and y = 1
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