Help me figure out this math question? Grade 1O Level on Square Roots?

[kaleigh girl]

Here's the question:
Simplify >>
23) 3?50 - 4?48

And this is what I did:
3?50 - 4?48
=3?25 ×2 - 2?16 × 2
Then this is where I don't know what to do-- did I even do the first step correctly?
I don't know what to do with the coefficients
If it was just ?50 from what I know that would be simplified as to 25?2 or is it 2?25? Help is very much appreciated! I want to learn how do this because I HAVE the ANSWER KEY =)

Another question:
?2(?10 + 4)

I did:
?2(?10 + 4)
=?20 +?8
=?5 × 4 + ? 4 × 2
Again, I don't know what comes next or even if I did this correctly...
How did you get 15 and 8?

[hayharbr]

3?50 - 4?48
=3?25 ×2 - 2?16 × 2

But 48 = 16X3 not 16X2 , and you switched the 4 in front to a 2, so it should be
3?50 - 4?48
=3?25 ×2 - 4?16 × 3
= 3 (5) ?2 - 4 (4) ?3

= 15?2 - 16?3

And the other, you only can multiply two square roots or two regular numbers; you can't multiply a regular number by a square root. So it is
?20 + 4?2
= ? 4x5 + 4?2
= 2?5 + 4?2

?50 for example can be rewritten as ?(25 x 2)
which then becomes ?25 times ?2
and since ?25 is just 5, it ends as 5?2