怎樣計長度(中學數)

畢氏定理: C^2 = A^2 + B^2

C = (x1,y1) (x2,y2) 的長度

A = X2 - X1 = 300 - 100 = 200

B = Y2 - Y1 = 300 - 100 = 200

So, C^2 = 200^2 + 200^2

C^2 = 80,000

C = 282.84

長度 = √[(x1 - x2)^2 + (y1 - y2)^2]

= √[(100 - 300)^2 + (100 - 300)^2]
= √(40000 + 40000)
= 282.843

(100+100)(300+300)