The diagonal of a rectangular trapezoid and its side are equal to find the length
The diagonal of a rectangular trapezoid and its side are equal to find the length of the midline if the height of the trapezoid is 2 cm and the side is 4 cm.
Given:
rectangular trapezoid ABCE,
AB = 2 centimeters,
AC = CE = 4 centimeters,
OH is the middle line.
Find the length of the midline OH -?
Decision:
1. Consider a right-angled triangle ABC.
Then, by the Pythagorean theorem (the square of the hypotenuse is equal to the sum of the squares of the legs):
AB ^ 2 + BC ^ 2 = AC ^ 2:
2 ^ 2 + BC ^ 2 = 4 ^ 2;
4 + BC ^ 2 = 16;
BC ^ 2 = 16 – 4;
BC ^ 2 = 12;
BC = 2√3 centimeters.
2. Consider the ACE triangle. It is isosceles since AC = CE. Let’s draw the height of the SC. She is the median. Then AK = KE = 2√3 centimeters. Therefore, the base AE = 4√3.
3. OH = (BC + AE): 2 = (4√ 3 + 2√ 3): 2 = 3√ 3 centimeters.
Answer: 3√ 3 centimeters.