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Greta says that the expression (2xa)+5 is the same as 2x(a+5). Is she correct?
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Since "a" is what's called "a variable", it can represent any number you want. "You have the power". So, just literally picking anything, let's say a=3. So, we would have:
(2x3)+5 and 2x(3+5)
Now, we always do what's in parenthesis first. So, for the left expression, we do 2x3 first. 2x3 = 6. Then, adding 5, 6+5 = 11. So, we have:
(2x3)+5 = 11 and 2x(3+5)
We just haven't done the right one yet. Now, we do that one. Always parenthesis first. So, 3+5 = 8. Then, we multiply that by the 2 at the beginning. 2x(8) = 16. So, we have:
(2x3)+5 = 11 and 2x(3+5)=16
So, Brooke, since 11 and 16 are different and not the same, then (2xa)+5 and 2x(a+5) can't be the same.
I hope this assist, Brooke. Good luck.
Posted by steveschoen on April 24, 2013 at 10:29 PM (Answer #1)
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