Answer:
-9y-2(2-7y)+4 expand the brackets using-2
Step-by-step explanation:
-9y-4+14y+4
arrange the like terms
-9y+14y-4+4
=5y becoz -4+4=0
ans=5y
Answer:

Step-by-step explanation:
First: multiply both sides by 4. 4 times c is 4c and the other sides cancels out as you are doing the inverse operation of division
Then, you have 
Subtract both sides by a squared
DO NOT TAKE THE SQUARE ROOT! This is because it is a squared plus 3b so you have to do the inverse of addition
From that you get 
Finally, divide both sides by 3.
You get 
There ya go! Hope this helped