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
The axis of symmetry is x=-1
Answer:
-4 =x
Step-by-step explanation:
5x+8=3x
Subtract 5x from each side
5x-5x+8=3x-5x
8 = -2x
Divide by -2
8/-2 = -2x/-2
-4 =x
Answer:
-14
Step-by-step explanation:
4+7=11 so therefore -3-11=-14
The ate more cheese pizza because 8/10 is greater than 5/12