Question

The function p(x) = 2x +1 determines how many pizzas need to be purchased for an after school meeting, where x is the number of students at the meeting. The club leader uses r(p(x)) to find the amount of money to bring for the pizza purchase. The function r(x) = 4x − 3. Solve for how much money to bring when there are 9 students in the meeting.

Answer 1

$p(x) = 2x + 9$
substitute the given number of students in the meeting

$p(x) = 2(9) + 9$
$r(p(x))$
wherever there is an x in the equation of r(x) substitute the p(x) equation
$r(x) = 4x - 3$

$4(2(9) + 9) - 3$
$4(18 + 9) - 3$
$4(27) - 3$
$108 - 3 = 105$

Answer 2

Answer:

r(p(x))=73

Step-by-step explanation:

To find the value of r(p(x)), the equation for p(x) which is 2x + 1, is substituted into every place that there is a x in the equation of r(x).

$r(x)=4x-3\\r(p(x))=4(2x+1)-3\\r(p(x))=8x+4-3\\r(p(9))=8(9)+4-3\\r(p(9))=73$