So, number 1)
3x - 2 (x+5)
When you have a number infront of brackets, you must multiple the brackets out, meaning: multiple the 2 by the x, then multiply the 2 by the 5. I don't exactly know how much you've learned about solving this, so im assuming you know BEDMAS. That's why we need to get rid of brakets first before doing anything else. This gives us:
3x - 2x - 10 (remember to keep track of you signs +/-)
x - 10 is your simplified answer.
When you have (4y - 3)(y - 2) you have to multiply the 4y by the y, then by the -2. Then multiply the -3 by the y, then by the -2.
(4y^2 means it is squared) This gives you:
-4 (4y^2 - 8y - 3y + 6)
Now you multiply the -4 by everything inside the brakets.
-16y^2 + 32y + 12y - 20
Collect like terms:
-16y^2 + 44y - 20
And that's your simplified answer.
Hope these two examples gives you an idea as to how you go about simplifying. For evaluating, all you have to do is sub in the value of the unknowns given to you into the expression and solve:
1. 5a-3b squared when a=-6 and b= 2
5(-6) - 3(2)
-30 - 6
-36 is your answer.
Hope that helped! Perhaps someone can further explain it better then myself if you still have questions