-9(7y-8y) + 12(6y-7y)=
please help me!!! I don't get it!
2006-10-16 14:57:36 · 8 answers · asked by Gracie Lady 2 in Education & Reference ➔ Homework Help
It's equivalent to -9 x 7y + 9 x 8y+12 x 6y - 12 x 7y (remember that - x - = + and - x + = - and that the multiplication is for all the members inside the ( ).
So you get:
-63y+72y+72y-84y
- 3y
The magic is that you can solve it in another way:
- 9 (-y) + 12 (-y) = 9 y -12 y (with the same rules)
- 3 y
2006-10-16 15:03:13 · answer #1 · answered by boule de gomme 4 · 0⤊ 0⤋
Just remember this formula in Math
PEMDAS or
Please Excuse My Dear Aunt Sally
PEMDAS stands for Parentheses, Exponents, Multiplication, Division, Addition, Subtraction.
For this formula you would do everything in the parentheses first and so on...
-9 (7y-8y) + 12 (6y-7y) =
-9 (-y) + 12 (-y)
9y - 12y [two - - make a positive, +/- make a neg.]
-3y
2006-10-16 22:12:36 · answer #2 · answered by Justwondering 1 · 0⤊ 0⤋
First you multiply -9 times 7y = -63y
then you multiply -9 times -8y = 72y
(remember when multiplying a negative and a positive...the answer will be negative. When multiplying two negatives the answer will be positive.)
Then multiply 12 times 6y = 72y
multiply 12 times -7y = -84y
Now your problem should look like this:
-63y + 72y + 72y -84y =
(combine like terms)
-3y
2006-10-16 22:07:00 · answer #3 · answered by rcpaden 5 · 0⤊ 0⤋
-9(7y-8y)+12(6y-7y)= subtract 12(6y-7y) from both sides
-9(7y-8y)=-12(6y-7y) distribute
-63y+72y=-72y+84y simplify
9y=12y no solution here, not possible This is an equation, as I see it, not an expression= sign. 007; where did that x come from?
2006-10-16 22:08:48 · answer #4 · answered by Anonymous · 0⤊ 0⤋
-9( 7y- 8y) + 12 (6y- 7y) = - 9 ( - y) +12 (- y) =9y-12y = - 3y ans.
2006-10-16 22:11:52 · answer #5 · answered by alpha 7 · 0⤊ 0⤋
-9(7y-8y) + 12(6y-7y)
-9(-y) + 12(-y)
9y + -12y
-3y far as i kno thats how to solve it.
2006-10-16 22:04:27 · answer #6 · answered by s_mollenk 1 · 0⤊ 0⤋
Order of operations. First solve inside the parenthesis. i.e., 7y-8y= -1y. Then do the multiplication. i.e., -9*(-1y) = 9y. Now you do the other half and add the two halves together. Good luck.
2006-10-16 22:02:43 · answer #7 · answered by bandl84 3 · 0⤊ 0⤋
-63y+72y+72y-84y=x
-63+72+72+84=x
-11+72+84=x
61+84=x
155=x
2006-10-16 22:02:15 · answer #8 · answered by Be my fan Please! 3 · 1⤊ 0⤋