Question

What is the length of JM in the given figure?

Answer 1

Answer: B. 30

Explanation:

When given a secant and a tangent, the formula is:

exterior of secant × secant = tangent²

KM × JK = LK²

10 × (JM + 10) = 20²

10JM + 100 = 400

10JM = 300

JM = 30