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put this solution on YOUR website!The sum of two numbers is 42. One number plus 2 times the other number is 57. What are the numbers?
x+y=42
x+2y=57
Lets solve by elimination;
so we will multiply the first equation by -1;
(-1)x+y=42
-x-y=-42
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Now we will add that equation to the second;
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y=15
now plug that into either original equation to find x;
x+15=42
x=27
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The sum of two numbers is 45. Their difference is 9. What are the numbers?
x+y=45
x-y=9
Since one variable will already be eliminated we will not need to multiply anything;
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2x=54
x=27
plug that into either equation for x;
27+y=45
y=45-27
y=18
:)
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