A 5mile cab ride costs$7.20 a 9 mile cab ride costs $11.60 find a linear equation that models a relationship between cost c and distance d?
Answers are
C =1.44 d +4.40
C=1.10 c +4.40
C=1.29 d+1.70
C=1.10 d +1.70
Thanks
If the formula is c=ad+b, then
5a + b = 7.20
9a + b = 11.60
Solve for a and b.
Or, note that as the distance increased by 4, the cost increased by 4.40
So, the slope is 1.1
That eliminates two of the choices right away. Now just see how much extra there is in each case when multiplying the distance by 1.1
Would the answers be c=1.10c+4.40
To find a linear equation that models the relationship between cost c and distance d, we need to determine the slope and y-intercept of the equation.
We have two data points:
- A 5-mile cab ride costs $7.20
- A 9-mile cab ride costs $11.60
To find the slope, we can use the formula:
slope = (change in y)/(change in x) = (change in cost)/(change in distance)
(change in cost) = $11.60 - $7.20 = $4.40
(change in distance) = 9 miles - 5 miles = 4 miles
So, slope = (4.40)/(4) = 1.10
To find the y-intercept, we can choose any data point and plug it into the equation y = mx + b, where m is the slope and b is the y-intercept.
Let's use the first data point: (5 miles, $7.20)
7.20 = 1.10(5) + b
7.20 = 5.50 + b
b = 7.20 - 5.50
b = 1.70
Therefore, the linear equation that models the relationship between cost c and distance d is:
C = 1.10d + 1.70
So, the correct answer is: C = 1.10d + 1.70
ummm. No
1.1(5) = 5.5
5.5+1.7 = 7.2
c = 1.1d + 1.7
Did you even try your formula against the data?