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justforgamies
Oct 6, 2011, 03:05 PM
I need help on these math problems! It says find each product or quotient. Express using exponents. ( I bolded the exponents!)
the questions are
*(5r then the exponent 3) (4r then the exponent is 4)
*10x exponent 3 y times (-2xy eexponent 2)
*8 exponent 4 over 8 exponent 3
*10 exponent 10 divided by 10 exponent 2
that's all and I need them by tonight no later please help!

Unknown008
Oct 7, 2011, 05:11 AM
Do you mean those:

5r^3\ \times\ 4r^4

10x^3y\ \times\ -2xy^2

\frac{8^4}{8^3}

\frac{10^{10}}{10^2}

If so, then what you do is multiply everything you have no problem with. And when you have multiplications of exponents, you add the exponents.

For example, the first one.

5r^3\ \times\ 4r^4 = 5\ \times\ 4\ \times\ r^3\ \times\ r^4 = 20\ \times\ r^{3+4} = 20r^7

Because if you expand the exponents here, what do you get?

r^3\ \times\ r^4 = (r\ \times\ r\ \times\ r)\ \times\ (r\ \times\ r\ \times\ r\ \times\ r)

Which makes a total of 7 r's and which mean r^7

For division, you apply the same concept, but subtract instead of adding. Can you post your answers? :)

justforgamies
Oct 25, 2011, 02:26 PM
Ok I don't understand ether of you guys sorry and I found out I don't have to do those problems thanks anyway!