Answer:
[tex]1. \quad p=\dfrac{-3q}{2}\\\\2. \quad b=\dfrac{4a+7}{2}, b=\dfrac{19}{2}\\\\3. \quad r=\dfrac{d}{t}\\\\4. \quad \text{D. 30}[/tex]
Step-by-step explanation:
1. Subtract p:
3p +3q -p = 0
2p +3q = 0 . . . . collect terms
2p = -3q . . . . . . subtract 3q
p = -3q/2 . . . . . . divide by the coefficient of p
__
2. Add 7 and divide by the coefficient of b:
4a +7 = 2b
(4a +7)/2 = b
Substitute for a to find the value of b.
(4(3) +7)/2 = b = 19/2
__
3. Divide by the coefficient of r:
r = d/t
__
4. The sum of length and width is half the perimeter:
15 + w = 90/2 = 45
w = 30 . . . . . . . subtract the length; the width is 30 units
