Hello :
f(r) = πr².... r <span> <span>><span> 0
</span></span></span>the domain is : <span>] 0; + ∞[<span> </span></span>
(-2)(-5)(-7)
(10)(-7)
-70
The product is -70
the correct question is
What values of b satisfy 3(2b+3)^2 = 36
we have
Divide both sides by 
take the square root of both sides
therefore
the answer is
the values of b are
First, sum up the total expenses for the original plan
Duque de Caxias + Campinas + Rio de Janeiro + Guarulhos = 242+185+193+120 = R$740
It is clearly over the intended budget. The average cost per itinerary is around R$200 so we will consider making a swap on either Duque de Caxias and Rio de Janeiro. Possible answers are (b) or (c)
for (b) Replace Duque de Caxias with Fortaleza, we will have
Fortaleza + Campinas + Rio de Janeiro + Guarulhos =
⇒ 201+185+193+120 = R$699 ⇒ This is exactly the budget intended for the trip
for (C) Replace Rio de Janeiro with Porto Alegre
Duque de Caxias + Campinas + Porto Alegre + Guarulhos =
⇒ 242 + 185 + 153 +120 = R$ 700 ⇒ This is over R$1
The answer is (b)
