Posted by **Anonymous** on Wednesday, December 7, 2011 at 8:35pm.

a car traveling at 30 meters per second begins to slow down at a constant rate. after 2 seconds its velocity is 16 meters per second. write an equation that represents the cars velocity v after t seconds

- geometry -
**Reiny**, Wednesday, December 7, 2011 at 8:49pm
Let the acceleration (really deceleration) be a

so v = at + c

when t=0 , v = 30

30 = 0 + c, --> c=30

so v = at + 30

when t=2, v = 16

16 = 2a + 30

2a = -14

a = -7

v = -7t + 30

- geometry -
**Reiny**, Wednesday, December 7, 2011 at 8:53pm
I just solved your question using Calculus, but I am not sure if you know Calculus, so ....

Treat your data two ordered pairs (0,30) and (2,16)

where the first coordinate is time and the second is velocity

slope = (30-16)/(0-2) = -7

so v = -7t + b , using the old y = mx + b format

but (0,30) must satisfy this

30 = 0 + b

b = 30

so v = -7t + 30 , as before

## Answer This Question

## Related Questions

- algebra - The formula below can be used to find the distances (d) traveled by an...
- algebra - The formula below can be used to find the distance (d) traveled by an ...
- algebra 1 - A ball is tossed upward with an initial velocity of 14.2 meters per ...
- Calculus - A team has been working to convert diesel-powered cars to run just as...
- Algebra - Use the given information to write a systems of equations, and then ...
- Math - A team has been working to convert diesel-powered cars to run just as ...
- calculus - A team has been working to convert diesel-powered cars to run just as...
- Algebra - The height, in meters, of a projectile can be modeled by h= -4.9t^2 + ...
- math - a launched rocket has an altitude, in meters, given by the polynimial h+...
- Algbrah - A launched rocket has an altitude in meters, given by the polynomial h...

More Related Questions