SOLUTION: Can you help my kid to solve this with steps Thank you -8(4+9x)=7(-2-11x

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Question 752119: Can you help my kid to solve this with steps
Thank you
-8(4+9x)=7(-2-11x
Found 2 solutions by unlockmath, josmiceli:
Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
This -8(4+9x)=7(-2-11x) we can expand to:
-32-72x=-14-77x
Add 72x and 14 to get:
-18=-5x
Divide by -5 to get:
x=18/5 or 3 3/5
Make sense?
RJ
www.math-unlock.com

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+-8%2A%284%2B9x%29=7%2A%28-2-11x%29+
----------------------
This problem is an example of
the associative rule.
The general rule is:
+a%2A%28+b+%2B+c+%29+=+a%2Ab+%2B+a+%2Ac+
-------------------------
+-8%2A4+-8%2A9x+=+-14+-77x+
Now divide each term on the left
and each term on the right by +-1+
The general rule for this is:
+-a%2F%28-1%29+=+a+
+32+%2B+72x+=+14+%2B+77x+
-----------------------
Now subtract +72x+ from both sides
+32+%2B+72x+-+72x+=+14+%2B+77x+-+72x+
+32+=+14+%2B+5x+
----------------
Subtract +14+ from both sides
+32+-+14+=+14+-+14+%2B+5x+
+18+=+5x+
-----------
Now divide both sides by +5+
+18%2F5+=+%285x%29%2F5+
+18%2F5+=+x+
-------------
You can check this answer:
+-8%2A%284%2B9x%29=7%2A%28-2-11x%29+
+-8%2A%284%2B9%2A%2818%2F5%29%29=7%2A%28-2-11%2A%2818%2F5%29%29+
+-8%2A%28+4+%2B+162%2F5+%29+=+7%2A%28+-2+-+198%2F5+%29+
+-32+-+1296%2F5+=+-14+-+1386%2F5+
Multiply both sides by +5+
+-160+-+1296+=+-70+-+1386+
+-1456+=+-1456+
OK
You don't have to follow this check exactly-
you should know that it's possible to check
your solutions
Good luck