Seven people can paint a bridge in 15 days.
a) How long will it take 3 people to paint the bridge?
b) The bridge was painted in t days, write down an expression, in terms of t, for the number of people needed to paint the bridge

a) 3 people will need 35 days to paint the bridge

b) p=105/t

Step-by-step explanation:

a)

We have 7 people each one is to work 15 days, so the bridge needs a total of 7(15) days of work

7(15)=105

Then we have 3 people each one is to work t days, altogether should do a total of 105 days of work

3(t)=105

Solve for t

t=35

b)

Substitute p for 3 in the second equation

p(t)=105

Solve for p

p=105/t

f(x) = x^3 -2x^2 -3x

x( x^2 -2x-3)

x( x^2 +x -3x -3)

x( x(x+1) -3(x+1))

x( x-3)( x+1)

so zeroes are 0, 3,-1

its (2) option