Answer:
42sq
Step-by-step explanation:
5:7
30 sq: x sq
30/5=6 sq for 1 of the ratio
6*7=42 sq for 7 of the ratio
Step-by-step explanation:
You said the other one would be the last haha just kidding I'm glad to help.
16. 
First, get rid of that parenthesis.

Now multiply both sides by 2 so that you can isolate k


19. 
This is a pretty easy one. If you didn't know, 121/11 is actually 11 :)

Simply multiply by 3 to isolate r :)


Solve for K by simplifying both sides of the equation, then isolate the variable.
K = 193