HKLM – rectangular trapezoid. Angle L = 150 °. Find HK if LM = 14cm.

1. Draw the perpendicular LN from the vertex L to the base of the NM.

2. We calculate the value of the angle MLN:

angle MLN = 150 ° – 90 ° = 60 °.

3. Calculate the length of the perpendicular LN through the cosine of the angle NLM.

LN / LМ = cosine of angle 60 ° = 1/2.

LN = LM x 1/2 = 14 x 1/2 = 7 centimeters.

4. According to the properties of the rectangle, its opposite sides are equal. Hence,

LN = KN.

side length KH = 7 centimeters.

Answer: the length of the side side of the KH is 7 centimeters.



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