F(x) = x^2 - 3x - 8
f(-2) = (-2)^2 - 3 (-2) - 8
f(-2) = 4 - 3 (-2) - 8
f(-2) = 4 + 6 - 8
f(-2) = 10 - 8
f(-2) = 2 ✅
2(3w-2+w)
=2(4w-2)
=8w-4
the formula for solving perimeters is 2(WL). so L=3w-2, because the question said the length is 2 units shorter than 3 times the width, and the width is w. so the final equation is <span>2(3w-2+w), and then you just have to simplify that </span>
L+S=8, L=8-S
500L+200S=2200, using L from above in this equation gives you:
500(8-S)+200S=2200
4000-500S+200S=2200
4000-300S=2200
-300S=-1800
S=6, and since L=8-S:
L=2
So Rita bought 2 large packets and 6 small packets.
