BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

2 circles are tangent each other and be x-axis above. What i

Expert replies
by Max@Math Revolution » Sat Mar 19, 2016 10:14 pm
Image

2 circles are tangent each other and be x-axis above. What is the slope of the line that passes through 2 centers of 2 circles?

A. 2/√96
B. 1/√6
C. 1/2√3
D. 1/√3
E. 2√6


* A solution will be posted in two days.
Join the discussion
Source: — Problem Solving |

by regor60 » Mon Mar 21, 2016 8:16 am
Join the discussion

by Max@Math Revolution » Mon Mar 21, 2016 5:21 pm
2 circles are tangent each other and be x-axis above. What is the slope of the line that passes through 2 centers of 2 circles?

A. 2/√96
B. 1/√6
C. 1/2√3
D. 1/√3
E. 2√6

Image


Just like the picture above, d=√96 is derived from d^2=(10^2)-(2^2)=96. Then, the slope of the line that passes through 2 centres=length of YZ/length of XZ. Thus, the slope is 2/√96. Therefore, the answer is A.
Join the discussion