If tan0=-3/4 and 0 is in quadrant IV, cos20= (33/25, -17/25, 32/25, 7/25, 24/25?) and tan20= (24/7, -24/7, 7/25, -7/25, 13/7, -1
Oksana_A [137]
Answer:
- cos(2θ) = 7/25
- tan(2θ) = -24/7
Step-by-step explanation:
Sometimes, it is easiest to let a calculator do the work. (See below)
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The magnitude of the tangent is less than 1, so the reference angle will be less than 45°. Then double the angle will be less than 90°, so will remain in the 4th quadrant, where the cosine is positive and the tangent is negative.
You can also use the identities ...
cos(2θ) = (1 -tan(θ)²)/(1 +tan(θ)²)
cos(2θ) = (1 -(-3/4)²)/(1 +(-3/4)²) = ((16-9)/16)/((16+9)/16)
cos(2θ) = 7/25
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tan(2θ) = 2tan(θ)/(1 -tan(θ)²) = 2(-3/4)/((16-9/16) = (-6/4)(16/7)
tan(2θ) = -24/7
Answer:
70910 (c)
Step-by-step explanation:
You move the decimal point to the right each time.
Answer:
Streamers are $2.50 each
Balloons are $1.50 each
Step-by-step explanation:
Make a system of equations
3s + 15b = 30
2s + 4b = 11
Solve by elimination: multiply the top equation by 2 and the bottom equation by -3.
6s + 30b = 60
-6s -12b = -33
18b = 27
b = 1.5
Plug in 1.5 as b to find s
3s + 15(1.5) = 30
3s +22.5 = 30
3s = 7.5
s = 2.5
The streamers are $2.50 and the balloons are $1.50
<h3>The formula that correctly relates H and L is H = L + 14.8</h3><h3>The high temperature is 83.7 degrees</h3>
<em><u>Solution:</u></em>
Let H represent the high temperature
Let L represent the low temperature
Given that,
<em><u>The coldest temperature in the city today was 14.8 degrees (Fahrenheit) lower than the hottest temperature</u></em>
L = H - 14.8
Rearrange,
H = L + 14.8
<em><u>If the low temperature was 68.9 degrees, what was the high temperature?</u></em>
L = 68.9
Then,
H = 68.9 + 14.8
H = 83.7
Thus the high temperature is 83.7 degrees
