Answer:
Identity (a) can be re-written as
which we already proven in another question, while for idenity (b)
step A is simply expressing each function in terms of sine and cosine.
step B is adding the terms on the LHS while multiplying the one on RHS.
step C is replacing the term on the numerator with the equivalent from the pithagorean identity 
Answer:23
Step-by-step explanation:
Left over is 456 minus total of A+B+C
456-334=122
C d are equal so 122/2=61
Answer:
∠4 and ∠3
∠4 and ∠5
∠3 and ∠6
Step-by-step explanation:
A pair of angles is said to be supplementary when the 2 angles add up to give 180°.
Two right angles add up to give 180°. Also, if we have two angles on a straight line, their sum = 180°, according to the linear pair property.
Thus, since m< 3 is given as 90°, m<4 = 90°.
m<4 + m<3 = 180°.
Therefore, <4 and <3 are supplementary.
<4 and <5, <3 and <6 are both linear pairs, therefore they are also supplementary.
