Help Help!!!

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Help Help!!!

by ramonsa » Tue Jun 02, 2009 3:51 am
What is the best way to do this problem?

Thanks.

Dan and Karen, who live 10 miles apart meet at a cafe that is directly north of Dan’s house and directly east of Karen’s house. If the cafe is 2 miles closer to Dan’s house than to Karen’s house, how many miles is the cafe from Karen’s house?
(A) 6
(B) 7
(C) 8
(D) 9
(E) 10
Source: — Data Sufficiency |

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by mike22629 » Tue Jun 02, 2009 4:59 am
Use pathagereom thereom:

Since it is directly north of one house and directly east of the other house, you know that it is a right triangle.

And since the cafe is 2 miles closer to dan than to other person set up equation like this:

a^2 + (a-2)^2 = 10^2

a = 8

Answer C.

You should know the general right triangles to make this problem easier:

6-8-10 (this one would be used for this problem)
3-4-5
And many more....
They should be in any prep company math book

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by aj5105 » Tue Jun 02, 2009 5:41 am
Distance between D to K : 10

Distance between C to D : x-2

Distance between C to K : x

DCK is right angled triangle. Using Pythagoras rule, we get x = 8


(C)