Fast ! the cost of go-karting is dollars for the
first ten laps around the track and
dollars for each additional lap. what is the
cost, in dollars, of go-karting for 17 laps?
(a) + ( × 7)
(b) + ( × 7)
(c) ( × 10) +
(d) 17 + +

you pay x for ten laps an you pay y for every additional lap you just multiply y by seven an add x

so all an all your answer would be (B) 

the polynomial is a perfect square trinomial of the form a^2-2ab+b^2:

option a. true

step-by-step explanation:

9x^2-12x+4

comparing with the form a^2-2ab+b^2

1.) a^2=9x^2

solving for a: square root both sides of the equation:

sqrt(a^2)=sqrt(9x^2)

a=sqrt(9) sqrt(x^2)

a=3x

2.) b^2=4

solving for b: square root both sides of the equation:

sqrt(b^2)=sqrt(4)

b=2

to be a perfet square trinomial 2ab must be equal to 12x. let's check:

2ab = 2 (3x) (2)

2ab = 12x

correct