For positive acute angles A and B, it is known that sin A= 21/29, and tan B = 28/45.
Find the value of cos(A – B) in simplest form.

sin(A+B) = sinAcosB+sinBcosA

if cosA = 9/41 then sinA =j40/41 It's a 9-40-41 right triangle

if tanB =21/20 then sinB =21/29 and cosB= 20/29 It's a 20-21-29 right triangle

plug those values into 1st equation above

sin(A+B) = 40/41(20/29) + 21/29(9/41) = ((40)20 + (21)9))/29(41) = (800+189)/1189 = 989/1189 = 0.832

or you could have just found A and B initially. cosA = 9/41 means A = 77.32 degrees

tanB = 21/20 means B = 46.4

A+B = 123.72

sin(123.72) = 0.832

Exact answer though without rounding is sin(A+B) = 989/1189 Step-by-step

explanation:

I don't know if that makes sense because its kind confusing! i'm sorry if it is hard to understand!

amount of oatypop that contains the prize = 40%

amount   of oatypop which doesn't contain the prize = (100-40)=60%

probability that hannah will win a prize

    = s +f s +f f s+ff   f s+ff f f s+ infinity.where f= failure,s= success

=   or 60%

probability that hannah only has to buy 3 or less boxes before getting a prize= (s) and ( f s) and (ff s) and (f f f s)

        = = 87.04 %  

step-by-step explanation:

proofs involving isosceles triangles often require special consideration because an isosceles triangle has several distinct properties that do not apply to normal triangles.(more about triangle types) therefore, when you are trying to prove that two triangles are congruent, and one or both triangles, are isosceles you have a few theorems that you can use to make your life easier.

step-by-step explanation:

an isosceles triangle has two congruent sides and two congruent angles. the congruent angles are called the base angles and the other angle is known as the vertex angle. ∠bac and ∠bca are the base angles of the triangle picture on the left. the vertex angle is ∠abc