Answer:
Step-by-step explanation:
Angles in a triangle add up to 180°
Angles in a straight line add up to 180°
Yep, this one seems sneaky and confusing. But it's not so bad if you remember the things you learned about parallel lines. (It can't be too tough ... I learned them
in 1954 and I still know how to use them.)
Look at the picture. Line ' l ' is parallel to line ' m ', and the horizontal line on the bottom (which is not labeled) is a transversal that cuts the parallel lines.
Did you learn that interior angles on the same side of the transversal are equal ?
I'm sure you did, although it may have a new name nowadays.
Anyway, with the help of that 'tool', angle-'B' and angle-'D' are equal. So . . .
(angle-A + angle-B) = 120
angle-B = 65
angle-A = 120 - 65 = <u>55 degrees</u>.
Answer:
75 - 35y / 3 + 2y = -4
( 75 - 35y + 6y ) / 3 = -4 [ Taking LCM ]
( 75 - 29y ) / 3 = -4
75 - 29y = -12
29y = 75+12
29y = 87
y = 3
hope that helps ✌
the arc length is calculated by the formula 
then 
or it can be calculated using the circumference of the circle since we have a semicircle the circumference 2πr must be divided by 2 С=2πr:2=πr =8π=<u>25,12</u>
