P=4.50s is the equation to use to determine p ...
because i believe y=mx+c
in this case
y is the price (p)
m is 4.50
x is the number of sunglasses (s)
there is no constant (c)
so p=4.50s
First you have to get x
5x-21=2x-6
3x=15
x=5
then substitute in any of the equations with x to get the y value:
y=2x-6
y=2(5)-6
y=4
so the answer is choice B
hope this helps !
We need to see the quadrilateral to answer
The equation is 10+4x=30(y) where x equals the number of hours