Vertical angles are equal to each other:
∠2 = ∠3
5 + 4y = 6y - 25
→ 30 = 2y
→ 15 = y
∠2 = 5 + 4y = 5 + 4(15) = 5 + 60 = 65
linear pairs equal 180:
∠1 + ∠2 = 180
→ ∠1 + 65 = 180
→ ∠1 = 115
The answer is B) 6xy and -16xy
Answer:
a) cos(α+β) ≈ 0.8784
b) sin(β -α) ≈ -0.2724
Step-by-step explanation:
There are a couple of ways to go at these. One is to use the sum and difference formulas for the cosine and sine functions. To do that, you need to find the sine for the angle whose cosine is given, and vice versa.
Another approach is to use the inverse trig functions to find the angles α and β, then combine those angles and find find the desired function of the combination.
For the first problem, we'll do it the first way:
sin(α) = √(1 -cos²(α)) = √(1 -.926²) = √0.142524 ≈ 0.377524
cos(β) = √(1 -sin²(β)) = √(1 -.111²) ≈ 0.993820
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a) cos(α+β) = cos(α)cos(β) -sin(α)sin(β)
= 0.926×0.993820 -0.377524×0.111
cos(α+β) ≈ 0.8784
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b) sin(β -α) = sin(arcsin(0.111) -arccos(0.926)) ≈ sin(6.3730° -22.1804°)
= sin(-15.8074°)
sin(β -α) ≈ -0.2724
Answer:
<em>y</em> = (5/3)<em>x</em> - 9
Step-by-step explanation:
First, find the slope (rise over run):
m = (-9 - (-14)) / (0 - (-3)) = (-9 + 14) / (0 + 3) = 5/3
Use the point-slope form equation with the given points (-3, -14):
y + 14 = (5/3)(x + 3)
or optionally in slope intercept form:
<em>y</em> = (5/3)<em>x</em> - 9
Answer: D. (-b,0)
applying coordinate geometry practice
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1. b.
2. a.
3. c.
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