A line segment is part of a line that has two endpoints and contains every point between its endpoints. A ray is a line that has one endpoint and continues infinitely in the other direction.
Answer: x=2π/3 and x=4π/3
Step-by-step explanation:
The equation we have is
. All we have to do is get cosine alone to find the 2 values of x.

Now that we have our cosine left, we can use our unit circle to figure out when does cosx=-1/2. Cosine is the x value of the coordinate.
x=2π/3
x=4π/3
Answer: Substitution
Step-by-step explanation:
GIVEN:
y=3x
2x+4y=12
Then, 2x+4(3x)=12
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Substitution: replacing one variable in terms of another variable.
As we can see from the given aspects, y=3x, and the conclusion expression has no y instead of 3x. This means it represented y in terms of x, which fits the definition of substitution that replaces one variable.
Hope this helps!! :)