Question

Cara drives for 4 hours at a rate of 45 miles per hour. Later, she drives for another 3 hours so that her total distance traveled for the day is 336 miles. Find the solution set for 4(45) + 3r = 336 given the replacement set {52, 53, 54, 55} to determine the rate at which Cara traveled during the second part of her trip.

(Points : 1)
52
53
54
55

Answer 1

help

Answer 2

4(45) + 3r = 336

what does 4(45) mean? any idea?

Answer 3

4*45

Answer 4

and 4*45= ?

Answer 5

180

Answer 6

so
4(45) + 3r = 336
is the same as
180 + 3r= 336
can you subtract 180 from both sides? what do you get?

Answer 7

156

Answer 8

what about the left side? in other words, write down the entire equation (or we will get lost)

Answer 9

3r=156?

Answer 10

close
180 + 3r= 336
180-180 + 3r = 336 -180
simplify both sides. 180-180 is 0 and 0+3r is 3r (adding 0 does "nothing")

3r = 156

Answer 11

52?

Answer 12

last step, divide both sides by 3.
on the left side 3/3 is 1 and you get r

Answer 13

yes
r= 156/3
r= 52