Answer:
r(x) = 135x + 59
The first choice
Explanation:
We have the number of children represented by p(x) = 64x + 21
the number of adults represented by q(x) = 38 + 71x
for x = number of days that the pool was opened during July.
function r(x) is suppose to represent the total number of children AND adults.
so r(x) = p(x) + q(x)
r(x) = (64x +21) + (38 + 71x)
r(x) = 64x + 71x + 21 + 38
r(x) = 135x + 59