Question

A 2-mi cab ride costs $4.25. A 7-mi cab ride costs $8.50. Which equation models the cost y of a cab ride that is x miles?
y = 0.85x - 2.55
y = 0.85x + 2.55
y = -0.88x + 2.55
y = 0.88x - 2.55

Answer 1

@skullpatrol

Answer 2

This question is based on the assumption that there is a fixed charge and a variable charge for the taxi

the variable charge is the 'cost per mile, and the fixed is an 'addon' regardless of distance

Answer 3

First work out the difference in cost between the 2 jouneys, and aklso the diffeneence in miles between the 2 jouneys

Post those numbers here and I will help you more

Answer 4

I think its B but im not sure

Answer 5

You can make two points from this info. (2, 4.25) and (7, 8.50)
The answer choices are in slope-intercept form y = mx + b where m is the slope.
So first find slope using the two points and the slope formula.
\[m = \frac{ y_2 - y_1 }{ x_2 - x_1 }\]
m = 8.5 - 4.25 / 7 - 2
m = 4.25 / 5
m = 0.85
Now we just need to find the y-intercept.
To do that, we can use point-slope form and substitute 0 for one of the x's.
point-slope form is \[y - y_1 = m(x - x_1)\]
Plug in the slope and either of the points.
\[y - 4.25 = 0.85(x - 2)\]
Now change the other x to 0 so that we can find the y-intercept b/c the x coordinate at the y-intercept is always 0.
\[y - 4.25 = 0.85(0 - 2)\]
When you solve that equation for y, you should get 2.55. :)
So your answer is y = 0.85 + 2.55

Answer 6

thanks c:

Answer 7

If you do the 2 things I wrote above, then I can help you

OR you can let someone else post the complete answer and not L:EARN anything

Answer 8

no I already thought it was B but she confirmed it

Answer 9

yes I did to the math... but I didn't know if I did everything right..

Answer 10

Well you have a good example above to follow through to check. the method :-)

Good luck

Answer 11

thanks I guess...