SOLUTION: Please help me solve this equation using the elimination method a+6b=7 a+2b=-1

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Question 811225: Please help me solve this equation using the elimination method

a+6b=7
a+2b=-1
Answer by erica65404(394) About Me  (Show Source):
You can put this solution on YOUR website!
The elimination method is when you add the equations together. you want to change the equations so a or b cancels out. To do this make them complete opposites.

a+6b=7
a+2b=-1

we want the a to cancels out. multiply the top equation by -1

-a-6b=-7

now add this to a+2b=-1

-a-6b=-7
a+2b=-1

now add

0a-4b=-8
-4b=-8
b=2

plug b into the first equation

a+6(2)=7
a+12=7
a=-5

a=-5 and b=2 is your answer.