wyork507@tg => YSITD: √[(F1x-x)+(F2y-y)^2]+√[(F2x-x)^2+(F2y-y)^2]=2c 這個(? #5ef20d1c25a5788234f6eaa9

wyork507@tg says to YSITD

√[(F1x-x)+(F2y-y)^2]+√[(F2x-x)^2+(F2y-y)^2]=2c 這個(?

at Tue, Jun 23, 2020 10:09 PM