How do I get the answer into another square root. for example- Square root of 6 times square root of 15 is 3 times the square root of 10. But on the Casio FX9750GII it comes up as a decimal, how do i change that?

You should feel happy that your calculator can perform some exact calculations. If you do not want the exact values you can press the SD key. You can also press SHIFT EXE rather than EXE alone.

To do them it REALLY helps if you remember Perfect Squares.it will make you quicker at doing these problems.

From this page http://www.gmathacks.com/mental-math/estimating-square-roots.html
I have copied a section below.

For these problems.....
you don't need the exact answer! An approximation is good enough

. Memorize Squares
For all sorts of reasons, you should memorize perfect squares at least up to 12^2 = 144. It helps to know additional round numbers, such as 15^2 = 225 and 25^2 = 625.
Once squares are burned into your memory, estimating square roots is easy. Let's go back to the square root of 39. The nearest perfect squares are 36 and 49, which are squares of 6 and 7, respectively. Thus, the square root of 39 is somewhere between 6 and 7. Since 39 is closer to 36 than to 49, the square root of 39 is closer to 6 than 7.
Sure enough, the square root of 39 is about 6.24. You will never see a problem on the GMAT where you need to know that the square root of 39 is 6.24. But you may well need to know that the square root of 39 is a little bigger than 6.

We all had to learn these at one time.

Give it a go friend :) You won't regret it.later on in life.

Press 6 . 0 0 5 g square-root

square-root is the g-shifted function of the leftmost key on the second row.

Square root of 39: Press 3 9 [square-root] =
[square-root] is the key just to the left of the divide key.

Cube root of 9482: Press 9 4 8 2 2nd [cube-root] =
[cube-root] is the shifted function of the 0 key.

For other roots, you can use the [nth-root] function, the shifted function of the key above the divide key. For example, to calculate the fourth root of 16, press 1 6 2nd [nth-root] 4 =

You don't want the square root. In this example, you want the sixth root.

Press 4 5 2nd [xth-root] 6 =

The xth-root is the shifted function of the y^x key, located just above the divide key.

Two ways:

2ND [square-root] ( 8 7 . 3 4 / 5 ) ENTER

8 7 . 3 4 / 5 ENTER then 2ND [square-root] 2ND ANS ENTER

The first sequence takes the square root of 87.34/5, the second sequence calculates 87.34/5 then takes the square root of the result.

The square root of a negative number is an imaginary number, and the TI-30XA does not deal with imaginary numbers.

However, the square root of -x is equal to i times the square root of x. So, to calculate the square root of -4, for example, press 4 square_root = and read 2. Thus the square root of -4 is 2i.

For square roots, use the square root key just to the left of the divide key. For example, 4 square-root = will give you 2.

The calculator doesn't have any way to store equations, scientific or otherwise. If you mean scientific notation, use the EE key just above the 7 key to enter exponents. For example, to enter 1.23x10^6, press 1 . 2 3 EE 6. For negative exponents, make sure to use the +- key to the right of the decimal point instead of the - key.

Use the toggle button above the enter key. It looks like 2 arrows

thanks it workd