Answer:56
Step-by-step explanation:
We already have the lengths of the given sides:
5+7=12
12+5=17
17+5=22
22+11=33
33+7=40
40+(5+11)=56
Alyssa earns $408 as commission
She sold shoes worth of $3,400
The formula to find commsion rate is

Where

The commission rate will be
F(x) = 2x^2 + 5x
f(3b) = 2(3b)^2 + 5(3b) = 2(9b^2) + 15b = 18b^2 + 15b