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Question 629436: Solve using the elimination method. If the system has no solution or an infinite number of solutions, state this.
-3x – 5y = 61
7x – 5y = -9
Please help I am so lost.
Answer by algebrahouse.com(1659)   (Show Source):
You can put this solution on YOUR website! -3x – 5y = 61
7x – 5y = -9
-1(-3x - 5y = 61 <--- multiplied top equation by -1}
7x - 5y = -9
3x + 5y = -61 <--- notice the 5y and -5y will now be eliminated, when added}
7x - 5y = -9
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10x = -70 {added the two equations together}
x = -7 {divided each side by 10}
7x - 5y = -9 {bottom original equation}
7(-7) - 5y = -9 {substituted -7, in for x, into bottom original equation}
-49 - 5y = -9 {multiplied 7 by -7}
-5y = 40 {added 49 to each side}
y = -8 {divided each side by -5}
x = -7 and y = -8
For more help from me, visit: www.algebrahouse.com
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