关於梯形的问题

2025-12-15 23:45:15
推荐回答(1个)
回答1:

(a)∵AB平行于CD,PA BQ分别垂直DC于P Q
∴ABQP为矩形
∴PQ=AB=11
QC=CD-DP-PQ=36-x-11=25-x
(b)x^2+h^2=25^2
(25-x)^2+h^2=30^2
∴25^2-x^2=30^2-(25-x)^2
25^2-x^2=30^2-25^2+50x-x^2
50x=25^2+25^2-30^2
x=7
h^2=25^2-x^2=25^2-7^2=576
h=24
(c) S=(11+36)*24/2=564