1st) 275+70-50 Lastly: Subtract -350 - 295 = - 55
275+70 = 345 The answer is - 55
345 - 50 = 295
10.99 x .25 is $2.7475. In dollars, you would round to the nearest hundredth so 2.75 is what the discount is. The discounted price is 10.99 - 2.75 which is $8.24
Answer: see proof below
<u>Step-by-step explanation:</u>
Given: cos 330 =
Use the Double-Angle Identity: cos 2A = 2 cos² A - 1
Proof LHS → RHS:
LHS cos 165
Double-Angle: cos (2 · 165) = 2 cos² 165 - 1
⇒ cos 330 = 2 cos² 165 - 1
⇒ 2 cos² 165 = cos 330 + 1
Given:
Divide by 2:
Square root:
Scratchwork:
Since cos 165 is in the 2nd Quadrant, the sign is NEGATIVE
LHS = RHS