Simplifying Radicals √ 12 + √ 75

Please help! I seriously don't know how to work this problem out. Please just dont give the answer but explain how to do it. Thank you <3 :)

√12+√75
Take a look at √12 and √75 separately.
√12 can be represented as √(4*3) or √4*√3
√75 can be represented as √(25*3) or √25*√3
We now have the following:
√4*√3 + √25*√3
√4 = 2;
2√3 + √25*√3
√25 = 5;
2√3 + 5√3
We can now add them together
2√3 + 5√3 = 7√3
7√3

you need to factor out the multiple

12=2*2*3

so, the two radical 2's make an integer 2
2sqrt(3)

75=3*5*5

the two radical 5's make an integer 5
5sqrt(3)

i don't know how to type a square root symbol, but I'll do the problem

sq rt 4 times sq rt 3 plus sq rt 25 times sq rt 3
2times sq rt 3 + 5times sq rt 3 = 7 times sq rt 3

√12+√75
2√3+5√3
7√3