Answer:
First option: cos(θ + φ) = -117/125
Step-by-step explanation:
Recall that cos(θ + φ) = cos(θ)cos(φ) - sin(θ)sin(φ)
If sin(θ) = -3/5 in Quadrant III, then cos(θ) = -4/5.
Since tan(φ) = sin(φ)/cos(φ), then sin(φ) = -7/25 and cos(φ) = 24/25 in Quadrant II.
Therefore:
cos(θ + φ) = cos(θ)cos(φ) - sin(θ)sin(φ)
cos(θ + φ) = (-4/5)(24/25) - (-3/5)(-7/25)
cos(θ + φ) = (-96/125) - (21/125)
cos(θ + φ) = -96/125 - 21/125
cos(θ + φ) = -117/125
Answer:
f(-2) = 9
Step-by-step explanation:
Given that,
f(x) = x² + x + 7
We need to find the value of f(-2).
Put x = -2 in the given function.
f(-2) = (-2)² + (-2) + 7
= 4-2+7
= 9
Hence, the value of f(-2) is equal to 9.
30 is 20% of 150
Working out percentage problems of the form "30 is 20 percent of what number?"
We have, 20% × x = 30
or,
20/100 × x = 30
Multiplying both sides by 100 and dividing both sides by 20,
we have x = 30 × 100/20
x = 150
If you are using a calculator, simply enter 30×100÷20, which will give you the answer.
<span>the probability of an event and the probability of its complement add up to 1
because the total events are the even it self and its compliment, so its probability equal to 1 because these are all the possible events that will occur. for example a coin toss, an event head will happen 0.5, and its complement is tails which will also happens 0.5</span>
Answer:
(-8,4)
Step-by-step explanation:
Given: 2x-3y=-28 and x+6y=16
solve for a variable and then substitute back into other equation
x + 6y = 16
x = 16 - 6y; now use this in the other equation
2x - 3y = -28; substitute into x
2(16 - 6y) - 3y = -28; distribute 2
32 - 12y - 3y = -28; combine y's
32 - 15y = -28; isolate 15y
32 + 28 = 15y; add the numbers
60 = 15y; divide by 15
y = 4
Now use this to plug into other equation
x + 6y = 16; y=4
x + 6(4) = 16;
x + 24 = 16; subtract 24 from both sides
x = -8
