Here we are:
Triangle PQR is equilateral, all the angles are 60, this means that triangle PSR is an isosceles triangle. 180-90=90 90/2=45 60-45=15
B=15
Hope this helps :)
6 notebooks per 1 package.
Work
Answer:
140
Step-by-step explanation:
Angle 4 is congruent to angle 2 by corresponding angles postulate. Therefore, angle 2 is also 40. Angle 2 and angle 3 are supplementary, or add up to 180 because they are on a straight line. 140 and 40 add up to 180 so angle 3=140 degrees