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:
$45
Step-by-step explanation:
70 + -25 = 45
10+9 x 8 = 100+50+2 (152)
38,496 rounded to the nearest thousand is 38,000.
Area of paralellogram=legnth times height
l=legnth
h=height
area=96
lh=96
h is 4 less than l
h=-4+l
sub
l(-4+l)=96
-4l+l^2=96
minus 96 both sides
l^2-4l-96=0
factor
(l-12)(x+8)=0
set to zero
l-12=0
l=12
l+8=0
l=-8, imossible, legnth cannot be negative, disreagard this soultion
legnth=12cm
