BFMracing
General Category => General Board => Homework Haven => Topic started by: conrad96 on June 01, 2010, 03:32:54 PM
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i am doing my home work and i came across this problem that i don't quite understand in a certian area. here it is
5t -8 (1+t)
-8(1)-8(t)+5t(1)+5t(t)
-8-8t+5t+...
im not sure if it would be 6t or still 5t or what. any ideas?
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anyone?
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Be patient, not all of us are online constantly. :)
Is the problem (5t - 8) (1 + t)
or
5t - 8 (1 + t)
There is a difference in the parentheses, and I'll tell you why.
Remember PEMDAS? ("Please Excuse My Dear Aunt Sally") This anagram tells you what the order of Operations is.
P - Parentheses
E - Exponents
M - Multiplication
D - Division
A - Addition
S - Subtraction
Do each of these in order, and that's how arithmetic works.
Now, back to your problem. I believe it should be
(5t - 8) (1 + t)
The distributive property says that you can multiply each monomial in a parentheses separately by a common monomial. What this means is that you can do exactly what is written down in your post. You multiply the first number on the left side, which in this case is 5t, by the first number on the right. Then multiply the first number on the left side with the second number on the right side, which would make 5t * t. Do the same for the next number, 8. If you expand this, it becomes:
5t(1) + 5t(t) - 8(1) - 8(t)
5t + 5t2 - 8 - 8t
5t2 - 3t - 8
That is the expanded version of your problem. I hope that makes sense. Remember that the distributive property only applies when you are multiplying a parentheses by some number (or in this case, another set of parentheses). Also remember your signs! ( + and - )
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thanks goalie, sorry i was impatient, when i can't figure something out i get frustrated, didn't even think of PEMDAS, i was taught in school to do the distributive property diferently, or i just wasn't paying attention. :P well that's ignorance for ya' any way, thanks again.
"Now you know and knowing is half the battle"
~ G.I joe ( jk jk :D )