Answer:
In linear expresiion 3 is the coefficient
X will be the variable and -15 will be the constant term.
Answer: see proof below
<u>Step-by-step explanation:</u>
Given: A + B + C = π → C = π - (A + B)
→ sin C = sin(π - (A + B)) cos C = sin(π - (A + B))
→ sin C = sin (A + B) cos C = - cos(A + B)
Use the following Sum to Product Identity:
sin A + sin B = 2 cos[(A + B)/2] · sin [(A - B)/2]
cos A + cos B = 2 cos[(A + B)/2] · cos [(A - B)/2]
Use the following Double Angle Identity:
sin 2A = 2 sin A · cos A
<u>Proof LHS → RHS</u>
LHS: (sin 2A + sin 2B) + sin 2C




![\text{Factor:}\qquad \qquad \qquad 2\sin C\cdot [\cos (A-B)+\cos (A+B)]](https://tex.z-dn.net/?f=%5Ctext%7BFactor%3A%7D%5Cqquad%20%5Cqquad%20%5Cqquad%202%5Csin%20C%5Ccdot%20%5B%5Ccos%20%28A-B%29%2B%5Ccos%20%28A%2BB%29%5D)


LHS = RHS: 4 cos A · cos B · sin C = 4 cos A · cos B · sin C 
Father and daguther together
father=180
father and daughter is 7 times daught
father+x=7x
180+x=7x
D is answer
and daughter=30lb
Method 1:

<h3>Answer: Henry will need 3 cups of water.</h3>
Method 2:


<h3>Answer: Henry will need 3 cups of water.</h3>
K/75 + 57.1 = 40.8
k/75 = 40.8 - 57.1
k/75 = -16.3
k = -16.3 • 75
k = -1222.5 or -1222 1/2
Hope it helps!