Answer: see proof below
<u>Step-by-step explanation:</u>
Given: A + B + C = π and cos A = cos B · cos C
scratchwork:
A + B + C = π
A = π - (B + C)
cos A = cos [π - (B + C)] Apply cos
= - cos (B + C) Simplify
= -(cos B · cos C - sin B · sin C) Sum Identity
= sin B · sin C - cos B · cos C Simplify
cos B · cos C = sin B · sin C - cos B · cos C Substitution
2cos B · cos C = sin B · sin C Addition
Division
2 = tan B · tan C
<u>Proof LHS → RHS</u>
Given: A + B + C = π
Subtraction: A = π - (B + C)
Apply tan: tan A = tan(π - (B + C))
Simplify: = - tan (B + C)
Substitution: = -(tan B + tan C)/(1 - 2)
Simplify: = -(tan B + tan C)/-1
= tan B + tan C
LHS = RHS: tan B + tan C = tan B + tan C 
Answer:
Step-by-step explanation:
Probability is the ratio of the required outcome to the total possible outcome
Total outcome = 75
Number of times target was hit (expected outcome) = 41
Pr(she will hit target)= 41/75
Next is to state in percent and u do that by multiplying the resulting fraction by 100
41/75 i n percent.
41/75×100
= 4100/75
= 54.67%
Hence the answer in percentage is 54.67%
Answer:
m∠A = 50°
m∠E = 50°
Step-by-step explanation:
7x - 17 and 2x + 8 are same side exterior angles. They have a sum of 180°.
7x - 17 + 2x + 8 = 180
9x - 9 = 180
9x = 189
x = 21
∠A and 7x - 17 are supplementary. ∠E and 2x + 8 are vertical angles.
m∠A + 7x - 17 = 180
m∠A + 7(21) - 17 = 180
m∠A + 147 - 17 = 180
m∠A + 130 = 180
m∠A = 50
m∠E = 2x + 8
m∠E = 2(21) + 8
m∠E = 42 + 8
m∠E = 50
It’s b :) haha i got it right
A cylinder's volume is =
π r² h,
and its surface area is =
2π r h + 2π r².
