Answer:
Step-by-step explanation:
Angles 1, 2, and 3 are supplementary (they add up to equal 180). If angles 1 and 3 are 20 each, then their sum in 40, making angle 2
180 - 40 = 140. If this central angle is 140 degrees, then the measure of the arc that it cuts off also measures 140 degrees. This is not to be confused with the arc length, which is not even remotely the same thing!
Sorry I can not help u right now
Answer:
The answer is B. 
Step-by-step explanation:
Because 
So the answer in this question is B.
Answer:
question 2 answer you wrote correct
question 3 answer is 20
Answer:
w-2u-v
Step-by-step explanation:
Given are three vectors u, v and w.
In R^2 we treat first element as x coordinate and 2nd element as y coordinate.
Thus we mark (1,2) in the I quadrant, (-3,4) in II quadrant and (5,0) on positive x axis 5 units form the origin.
b) 
We have to find the values of a and b
]
Equate the corresponding terms

Divide II equation by 2 to get

Eliminate a
-5 = 5b: b=-1
a=-2
Hence
w = 2u-v