<span>If M is the midpoint of CD, CM = 2x+3 and MD = 3x-6, then:
MD = CM
3x - 6 = </span>2x + 3
3x - 2x = 3 + 6
x = 9
CM = 2x+3 = 2*9+3 18+3 = 21
MD = CM = 21
CD = CM + MD = 21 + 21 = 42
Trigonometric functions which are related by having the same value at complementary angles are called cofunctions. Cofunctions of complementary angles are equal.
A. csc 20' = csc(90-70)=sec 70
B. cos 87' = cos (90-3)=sin 3'
C. csc 40' = csc(90-50) =sec50'
D. tan 15' = tan(90-75)= cot 75'
Among all the option c is not correct.
Option C is false.