In the given parallelogram, BE and CE are angle bisectors. If m∠A = 70°, find m∠BEC.

∠BEC=90°

Step-by-step explanation:

∠A=∠BCD and ∠ABC=∠D because opposite angles in a parallelogram are equal.

∠A=∠BCD=70

All angles in a quadrilateral add to 360:

∠A+∠ABC+∠BCD+∠D=360

∠ABC+∠D=360-140=220

∠ABC=∠D=110

Since ∠ABC=∠ABE+∠EBC, and ∠ABE=∠EBC (because BE is an angle bisector), ∠EBC=55.

Since ∠BCD=∠BCE+∠ECD, and ∠BCE=∠ECD (because CE is angle bisector), ∠BCE=35.

All angles in a triangle add to 180:

∠BCE+∠EBC+∠BEC=180

35+55+∠BEC=180

∠BEC=180-90

∠BEC=90°

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."

570, the answer is 570, hope it