As shown in the figure, in the quadrilateral BCDE, angle c = angle, bed = 90 degree, angle B = 60 degree, extend CD, be, get the right triangle ABC The length of BC

As shown in the figure, in the quadrilateral BCDE, angle c = angle, bed = 90 degree, angle B = 60 degree, extend CD, be, get the right triangle ABC The length of BC

According to the Pythagorean theorem, ad = 2DE = 2, ab = 2BC according to the Pythagorean theorem, a = 30 & # 186; [according to the right triangle 30 & # 186; the opposite side = half of the hypotenuse] ad = 2DE = 2, ab = 2BC according to the Pythagorean theorem, a = 30 & # 186; [according to the right triangle 30 & # 186; the opposite side = half of the hypotenuse] ad = 2DE = 2, ab = 2BC # 178; + AC # 178;; (2BC) & # 178; = BC # 178; + (2 + 2) & # 178; 3bC # 17

As shown in the figure, there is a right triangle with an angle of 60 degrees. After cutting along one of its median lines, the quadrilateral that cannot be assembled is ()
A. A rectangle with unequal adjacent sides B. an isosceles trapezoid c. a diamond with an acute angle D. a square

As shown in the figure, this triangle can be assembled into three shapes as shown in the figure: (1) it is a rectangle, if ∵ has an angle of 60 °, the other angle is 30 °, this rectangle is a rectangle with unequal adjacent sides; (2) it is a diamond with two angles of 60 °; (3) it is an isosceles trapezoid