Answer:
KL = 7
Step-by-step explanation:
Given 2 secants from an external point to the circle, then
The product of the measures of one secants external part and the entire secant is equal to the product of the other secant's external part and the entire secant, that is
MN(MN + NC) = ML(ML + LK), that is
8(8 + 10x) = 9(9 + 7x) ← distribute both sides
64 + 80x = 81 + 63x ( subtract 63x from both sides )
17x + 64 = 81 ( subtract 64 from both sides )
17x = 17 ( divide both sides by 17 )
x = 1
Hence
KL = 7x = 7 × 1 = 7
