Multiply. write answer is lowest form.?

Multiply. write answer is lowest form.

-11y^4 times 49y^6

_____ _______

7y^4 times 121y

it's a fraction and the line is seperating top from bottom.

i did -1.11.7.7.y^4.y^6

______________ then i did 11.7y^5 times -7y^5

7.11.11.y.y^4 ______ ______

11.7y^5 11

I don't get how i got y to the 5th powered? or what to do next

Re: Multiply. write answer is lowest form.?

So this is $\displaystyle \frac{-11y^4}{7y^4}\frac{49y^6}{121y}$?

I presume you immediately noticed that $\displaystyle 49= 7^2$ and $\displaystyle 121= 11^2$.

Quote:

i did -1.11.7.7.y^4.y^6

Okay, that is $\displaystyle -1.11.7.7y^10$ because $\displaystyle y^ay^b= y^{a+ b}$

in the numerator

and you have 7.11.11.y.y^4 which is $\displaystyle 7.11.11.y.y^= 7.11.11.y^{4+1}= 7.11.11.y^5$

in the denominator.

$\displaystyle \frac{-1.11.7.7.y^{10}}{7.11.11.y^5}$ and you should see that one "11" in both numerator and denominator will cancel and that one "7" in both numerator and denominator will cancel so you have

$\displaystyle \frac{-1.7.y^{10}}{11.y^5}$.

Now, as always in mathematics, you can do that in several different ways. First, you can write, or imagine, that "$\displaystyle y^{10}$" as 10 separate "y"s in the numerator and the "$\displaystyle y^5$" in the denominator as 5 separate "y"s in the denominator and cancel 5 of them leaving "$\displaystyle y^5$" in the numerator. Or you could "move" that "[itex]y^5[/itex]" into the numerator where it becomes "$\displaystyle y^{-5}$". And then, of course,

you have $\displaystyle y^{10}y^{-5}= y^{10+(-5)}= y^5$. Finally, you could use the exponent law derived in that way- $\displaystyle y^a/y^b= y^{a- b}$ so that $\displaystyle y^{10}/y^5= y^{10- 5}= y^5$.