$\large{选择高}$

演示

a = 5.4 (slider from 4 to 6)
h = 3.1 (slider from 2 to 4)
j = 2 (slider from 2 to a)
A: (0, 0)
B: A + (2, h)
C: B + (a, 0)
D: A + (a, 0)
E: A + (j, 0)
F: E + (0, h)
k = 0 (slider from 0 to 1, step 0.001)
G = Point(Segment[A, D], k)
H: G + (j, 0)
I: H + (0, h)
J: I - (j - 2, 0)
g = Segment(E, F)
α = Angle(D, E, F)
q1, g_1, h_1, i, j_1 = Polygon(G, H, I, J)
q2, c, d, e, f = Polygon(C, D, E, F)
text1 = Text("a", A + (j + 0.1, 0), false, true)
text3 = Text("h", Midpoint[E, F] + (-0.8, 0.5), false, true)
n = 0 (slider from 0 to 3, step 1)
text2 = Text("S=ah", F + (0.2, 1), false, true)

Tool: 简易坐标系
请选择原点，分别输入：x最小、最大值，y最小、最大值
Input: A, a, b, c, d
Output: B, C, O, u, v

$\huge\textcolor{}{x}$

$\huge\textcolor{}{y}$

$\Large\textcolor{}{O}$

A: (0, 0)
u = Vector(A + (a - 1, 0), A + (b + 1, 0))
v = Vector(A + (0, c - 1), A + (0, d + 1))
B: A + (b + 1, 0)
C: A + (0, d + 1)
O: A