D. x-6
That is the correct answer.
Answer:
- sin(2x) = -4/5
- cos(2x) = 3/5
- tan(2x) = -4/3
Step-by-step explanation:
It may be easiest to start with tan(2x).
tan(2x) = 2tan(x)/(1 -tan(x)²)
tan(2x) = 2(-1/2)/(1 -(-1/2)²) = -1/(3/4)
tan(2x) = -4/3 . . . . . still a 4th-quadrant angle
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Then cosine can be found from ...
cos(2x) = 1/√(tan(2x)² +1) = 1/√((-4/3)²+1) = √(9/25)
cos(2x) = 3/5
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Sine can be found from these two:
sin(2x) = cos(2x)tan(2x) = (3/5)(-4/3)
sin(2x) = -4/5
It would be 23.5 idk if your aloud to do that
or 141/6
Answer:
m<ABC = 45
m<DBC = 34°
Step-by-step explanation:
Given:
m<ABD = 79°
m<ABC = (8x - 3)°
m<DBC = (5x + 4)°
Step 1: Generate an equation to find the value of x
m<ABC + m<DBC = m<ABD (angle addition postulate)
(8x - 3) + (5x + 4) = 79
Solve for x
8x - 3 + 5x + 4 = 79
13x + 1 = 79
Subtract 1 from both sides
13x + 1 - 1 = 79 - 1
13x = 78
Divide both sides by 13
x = 6
Step 2: find m<ABC and m<DBC by plugging the value of x into the expression of each angle
m<ABC = (8x - 3)°
m<ABC = 8(6) - 3 = 48 - 3 = 45°
m<DBC = (5x + 4)°
m<DBC = 5(6) + 4 = 30 + 4 = 34°
Step-by-step explanation:
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