00:01
So the cost of renting a car is $47 per week plus $0 .25 per mile travel during that week.
00:10
An equation to represent the cost would be y equals 47 plus 0 .25x, where y is the total cost and x is the number of miles you travel.
00:19
So problem a, what is the cost if you travel 57 miles? let's do that one first.
00:26
So i'm going to rewrite the equation.
00:33
Right what does it cost to be trial 57 miles so like i said earlier here and i'll go ahead and label this x is miles and y is total the total amount d so if we call it's 57 miles we can just replace this x with 57 and calculate y so this is just 0 .25 times 57 and i'm going to put this into my calculator this is all equal to 61 .25 so that's the total cost when you you travel 57 miles.
01:14
Part b.
01:15
If your cost was 6450, how many miles did you drive? so this is the opposite of the previous problem because in this one we're giving given the total.
01:25
So we're given the y value we want to find the x value.
01:28
So the total was 6450 and we want to find x.
01:34
So i'm going to rewrite the equation like this.
01:38
I'm going to subtract 47 from both sides.
01:41
So 6450 minus 47.
01:46
Is 17 .5.
01:50
Now i'm going to multiply both sides by 4, and i'm doing this because 0 .25 is the same as 1 .4th...