Answer:
x=20
Step-by-step explanation:
2(x+10)=60
distribute 2 by multiplying numbers in parenthesis
2x+20=60
subtract 20 from both sides
2x=40
divide both sides by 2
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x=20
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(C) sin(-r) = -a
(D) sin(r) = -a
<u>Explanation:</u>
The unit circle definition allows us to extend the domain of sine and cosine to all real numbers. The process for determining the sine/cosine of any angle θ is as follows:
Starting from (1,0) move along the unit circle in the counterclockwise direction until the angle that is formed between your position, the origin, and the positive x-axis is equal to θ.
- sin θ is equal to the y-coordinate of your point, and
- cosθ is equal to the xxx-coordinate.
In the question, sin(-r) = -a and sin(r) = -a is equal to the x-coordinate, thus they are not correct.
An image is attached for reference.
Answer:
Step-by-step explanation:
We can add the same quantity to both sides of the equations, and still have an equivalent equation. Let's add to both sides, then sum like terms
(this is the rule that allows us to move items from one side do the other of the equal sign by changing its sign)
At this point we have a solution, let's replace it to verify
12 = x² - x
12 - 12 = x² - x - 12
0 = x² - x - 12
x² - x - 12 = 0
x = <u>-(-1) +/- √((-1)² - 4(1)(-12))</u>
2(1)
x = <u>1 +/- √(1 + 48)</u>
2
x = <u>1 +/- √(49)
</u> 2
x = <u>1 +/- 7</u>
2
x = 0.5 +/- 3.5
x = 0.5 + 3.5 x = 0.5 - 3.5
x = 4 x = -3
<u />
Answer:
-58
Step-by-step explanation:
We are to find tfhe dot product of u=<-8,9> and v=<5,-2>
u*v = <-8,9>*<5,-2>
u*v = -8(5)+9(-2)
u*v = -40 - 18
u*v = -58
Hence the product of the vectors is -58