SOLUTION: -(8y+3)-(-7y-4)=-3 Would this be correct -8y+3=7y-4=-3 My e-mail is collinscora@yahoo.com

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Question 326829: -(8y+3)-(-7y-4)=-3 Would this be correct -8y+3=7y-4=-3 My e-mail is collinscora@yahoo.com
Answer by jessica43(140) About Me  (Show Source):
You can put this solution on YOUR website!
This is not quite correct.... to solve this one, you first need to distribute the negatives and FOIL.
-(8y+3) is the same as -1*(8y+3)
So you need multiply each value in the parentheses by -1 and then add them:
(-1)*(8y+3) = (-1)*(8y) + (-1)*(3) = -8y + (-3) = -8y - 3
You need to do the same for the rest of the problem:
-(-7y-4)= (-1)*(-7y-4) = (-1)*(-7y) + (-1)*(-4) = 7y + 4
Now that you see how it is done in parts , let's do the whole thing:
-(8y+3)-(-7y-4)=-3
((-1)*(8y+3)) + ((-1)*(-7y-4)) = -3
(-8y - 3) + (7y + 4) = -3
-8y - 3 + 7y + 4 = -3
Now combine the like terms:
-8y - 3 + 7y + 4 = -3
-y + 1 = -3 (-8y + 7y = -y; -3 + 4 = 1)
-y = -4
y = 4
So your answer is y = 4.