√27x^2y - √45xy^2 + √108x^2y - √125xy^2
a. xy√15xy
b. 9x√3y - 8y√5x
c. √135x^2y - √170xy^2
d. 3x√15y - 4y√5x

Question

mathteacher1729 · Answer

Is this from something which is being graded?

anonymous · Answer

Yes, but I am home schooled and don't understand this lesson.

mathteacher1729 · Answer

Do you know how to "simplify a radical"? 

$$\begin{align}\sqrt{27}&=\sqrt{9\cdot3}\&=\sqrt{9}\sqrt{3}\&=\fbox{$3\sqrt{3}$}\end{align}$$

mathteacher1729 · Answer

Can you do something similar to the other radical expressions?

mathteacher1729 · Answer

http://www.mathtv.com/videos_by_topic This website is AMAZING. The old guy is the best. Click "Algebra, Simplifying Expressions, then with radicals". There are like 10 video examples.

anonymous · Answer

I know a little bit about simplifying radicals, I can add and subtract ones like these: '4√2 + 7√2 - 3√2"

anonymous · Answer

Thank you (:

mathteacher1729 · Answer

So basically with this problem, what you wanna do is this:  Simplify all the radicals and combine "like radicals" .

mathteacher1729 · Answer

so go one step at a time, try it with $$\sqrt{45}$$

anonymous · Answer

√45 = (9 x 5) 
= 3√5

mathteacher1729 · Answer

Yup! Keep going with the rest. :)