The question of trapezoids, the question about trapezoids

Trapezium. A trapezoid is a set of quadrilaterals in which one set of opposite sides is parallel and the other set of opposite sides is not parallel. The two parallel sides are called the bottom edge of the trapezoid, and the long side is called the lower bottom; The two sides that are not parallel are called the waist; The perpendicular segment sandwiched between the two bases is called trapezoidal height.

A trapezoid with one waist perpendicular to the bottom is called a right-angle trapezoid, and a trapezoid with two equal waists is called an isosceles trapezoid. Isosceles trapezoidal is a special trapezoid, and its determination method is similar to that of isosceles triangle.

This paragraph] is isosceles trapezoidal in nature.

1 The two waists of an isosceles trapezoid are equal 2 The two base angles of an isosceles trapezoid on the same base are equal 3 The two diagonals of an isosceles trapezoid are equal 4 The isosceles trapezoid is an axisymmetric figure, and the axis of symmetry is the line where the line connecting the midpoints of the upper and lower bases is located 5 The median line of the isosceles trapezoid (the same is true for this non-isosceles trapezoid) (the line connecting the midpoints of the two waists is called the median line) is equal to one-half of the sum of the upper and lower bases 6There is a trapezoid with an angle of 90° that is a right-angle trapezoidal Note: In some cases, the upper and lower bases of the trapezoids are distinguished by length, rather than determined by position, and the shorter bottom is called the upper bottom, and the longer bottom is called the lower bottom.

this paragraph].

1 A group of quadrilaterals with opposite sides parallel and another set of quadrilaterals with opposite sides that are not parallel is a trapezoid (a set of quadrilaterals with parallel and unequal opposite sides is a trapezoid) 2 A trapezoid with two waists equal is an isosceles trapezoid 3 A trapezoid with two equal angles on the same base is an isosceles trapezoid 4 A trapezoid with an inner angle of right angles is a right-angle trapezoid 5 A trapezoid with equal diagonals is an isosceles trapezoid 6The median line of the trapezoid is equal to half of the sum of the upper bottom and the lower bottom, and is parallel to the upper and lower bottoms.

Circumference and area of this paragraph.

The area formula of the trapezoid: (upper bottom + lower bottom) height 2. Isosceles trapezoidal area formula:

The median line height is represented by letters: (a+b) h2 or l·h The formula for the circumference of the trapezoid: upper bottom + lower bottom + waist + waist is represented by letters:

a+b+c+d

The top and bottom edges are parallel, and the other two sides are not parallel.

Pass D as DF perpendicular to BC and BC over F

Angle c = 45 degrees, then the triangle CDF is an isosceles right triangle.

So cf 2

Because the angle abc = 90 degrees, AD BC

Therefore, the ab cripping clan is straight to BC

So abfd is rectangular.

So bf=ad=1

bc=bf+fc=3

Because BE is perpendicular to CD, the angle c = 45 degrees.

Therefore, the triangular BCE is a Qi Xiao isosceles right-angled three-trillion buried angle.

So be=3 2 times the root number 2

1. EF is the median line of this trapezoid, parallel and equal to half of the sum of the upper and lower bases.

Proof: Dm is parallel to AB and EF is at point H.

The quadrilateral abmd is a parallelogram, so EH is parallel and equal to half of AD+BM.

In the triangular DCM, F is the midpoint of the CD, and FH is parallel to the MC, so FH is the median line of the triangular DMC.

So FH is equal to half of cm.

The two equations are added to give EF parallel and equal to half of AD+BC.

Because 45°. So (top bottom + bottom bottom) = 10cm.

So s trapezoidal = 10 10 2 = 50 square centimeters, so s = 50 2 = 25 square centimeters.

Your adoption is an affirmation of me.

As you can see from the figure, both blank parts are right-angled triangles, so the sum of the upper and lower bases of the trapezoid is equal to the height of the trapezoid.

Therefore, the area of the trapezoid is 10*10 2 = 50 square centimeters.

The area of the shaded part is 50 2 = 25 square centimeters.

The vertices of the right angles of the shaded part should be bisected by 10cm, and the area of the shadowed part = 10 2*10 2 = 25

Because the length of the lower bottom and the upper bottom of the two vertices of the spare wheel is 6 and the imitation letter 8, and the upper bottom is 10, so these three sides form a right triangle. The height of the implicit trapezoid is the height on the hypotenuse of this right triangle (which can be seen at once by drawing a sketch on paper with a pen).

So the height of the trapezoid is: 6 8 10=

Am I reading it wrong?

The trapezoidal area formula is s=(upper bottom + lower bottom) * height 2

The bottom is auspicious with = 2s high sell shout - top bottom.