Answer:
C) 
Step-by-step explanation:
By the cos double angle formula, we know
Substituting
into the formula, we get
.
The answer is C.
Answer:
Option 3
Step-by-step explanation:
we are given the graph of a parabola
with vertex at (0,-1) and symmetrical about y axis and also open up.
Hence the equation of the graph would be transformation of 
by a vertical shift of 1 unit down.
So new equation after transformation would be

Or
Hence option 3 is right choice.
Verify:
Put Solving the equation we get


In the graph x intercepts are the same as -1 and 1
Hence our answer is right.
Answer:
x+20
Step-by-step explanation:
As we can see n the diagram, there are parallel traversals and one line, and the two angles given are same-side interior angles. We know that when there is parallel traversal, and we have same side interiors, the sum of the measure of the two angles are supplementary. Supplementary means 180 degrees, or a straight line.
So we plug everything in and we have 4x+5x=180 degrees
4x+5x=9x, so 9x=180
We divide by 9 on both sides to get the value of x, which is 20
Hope it helps!
Answer: 2 1/2
Step-by-step explanation: Divide using long division. The whole number portion will be the number of times the denominator of the original fraction divides evenly into the numerator of the original fraction, and the fraction portion of the mixed number will be the remainder of the original fraction division over the denominator of the original fraction. Hope this helps!! PLZ mark me!!!