Distribute (16x + 20n + 16 * 18)
Simplify 16 * 20n to 320n (320n + 16 * 18)
Simplify 16 * 18 to 288
Therefore in conclusion the answer would be 320n + 288.
Check the picture below.
about ∡QML
well, QM is a diameter chord, and LM is a tangent line, the point of tangency is always a right-angle, as you see it in darkred there.
about ∡PMN
well, first off, let's notice the inscribed angle of 27°, by the inscribed angle theorem, that means the intercepted arc is twice that much, as you see it there in green.
QM is a diameter, so the arcQPM is 180°, if we subtract the 54° from arcPQ, we're left with the arcPM you see there of 126°.
by the tangent-chord angle theorem, ∡PMN is half of arcPM.
I think the answer is going to be a
18 + 22 + 23 + 24 + 25 + 26 + 30= 168
168/7= 24
the missing number is 24
Good Luck! XD