Question

What is the measure of m<1 will ensure that the rail is parallel to the bottom of the staircase?

Answer 1

You can observe that angle 1 and angle with 47° are inside a parallelogram.

Consider that the sum of the internal angles of a parallelogram is 360°.

Moreover, consider that the angle at the top right of the parallogram is congruent with the angle of 47°, then, such an angle is if 47°.

Consider that angle down right side is congruent with angle 1, then, they have the same measure.

You can write the previous situation in the following equation:

47 + 47 + ∠1 + ∠1 = 360 simplify like terms

94 + 2∠1 = 360 subtract both sides by 94

2∠1 = 360 - 94

2∠1 = 266 divide by 2 both sides

∠1 = 266/2

∠1 = 133

Hence, the measure of angle 1 is m∠1 = 133°