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## Homework Statement

Two cars are facing each other on a long straight airport runway. They are initially separated by a distance of 1 km. Car A begins to accelerate towards the other car at a uniform 0.5 ms^-2. Ten seconds later car B begins to move towards the other car with a uniform acceleration of 1 ms^-2. When and where do the two cars meet?

Car A:

u=0

v=?

a=0.5

t=t

s=1000-x

Car B:

u=0

v=?

a=1

t=t-10

s=x

## Homework Equations

s=vt

s=ut + 1/2at^2

s=vt-1/2at^2

v^2 = u^2 + 2as

## The Attempt at a Solution

1000-x= 0(t)+1/2(0.5)(t)^2

x= 0(t)+1/2(1)(t-10)^2[/B]

1000-x+x=.25t^2+0.5(t-10)^2

1000=.25t^2+0.5t^2-10t+50

0=.75t^2-10t-950

t=42.88 or -29.52

t=42.88

Which is wrong.

My confusion is coming from how to set equations equal to each other, not only in this problem.