Question

Let C be a circle of radius $\sqrt 20\ cm.$ Let $L_1, L_2$ be the lines given by $2x − y −1 = 0$ and $x + 2y−18 = 0$, respectively. Suppose that $L_1$ passes through the center of C and that $L_2$ is tangent to C at the point of intersection of $L_1$ and $L_2$. If (a,b) is the center of C, which of the following is a possible value of $a + b$?

• A. 11
• B. 17
• C. 8
• D. 20
• E. 14

Answer 1

Answer: (B)

17

Answer 2

The correct option is (B): 17.