Question

help me solve these two question.
1. solve for p
3(p+q)=p
a. q= -2/3p
b. q= -3/2p
c. p=-2/3q
d. p= -3/2q

2. solve for b, then find the value of b when a=3.
a. -9/2
b. 5/2
c. 19/2
d. 17

check if these answers are correct.

3. solve for r
d=rt
a. r= dt
b. r= t/d (my answer)
c. d/t
d. r=d-t

4. find the width of a rectangle with a perimeter of 90 and a length of 15.
a. 90
b. 15
c. 45
d. 30 ( my answer )