如圖(1),AB=7cm,AC⊥AB,BD⊥AB垂足分別為A、B,AC=5cm.點(diǎn)P在線段AB上以2cm/s的速度由點(diǎn)A向點(diǎn)B運(yùn)動(dòng),同時(shí)點(diǎn)Q在射線BD上運(yùn)動(dòng).它們運(yùn)動(dòng)的時(shí)間為t(s)(當(dāng)點(diǎn)P運(yùn)動(dòng)結(jié)束時(shí),點(diǎn)Q運(yùn)動(dòng)隨之結(jié)束).
(1)AP=
2t
2t
cm,BP=
7-2t
7-2t
cm(用含t的代數(shù)式表示);
(2)若點(diǎn)Q的運(yùn)動(dòng)速度與點(diǎn)P的運(yùn)動(dòng)速度相等,當(dāng)t=1時(shí),△ACP與△BPQ是否全等,并判斷此時(shí)線段PC和線段PQ的位置關(guān)系,請分別說明理由;
(3)如圖(2),若“AC⊥AB,BD⊥AB”改為“∠CAB=∠DBA”,點(diǎn)Q的運(yùn)動(dòng)速度為x cm/s,其它條件不變,當(dāng)點(diǎn)P、Q運(yùn)動(dòng)到何處時(shí)有△ACP與△BPQ全等,求出相應(yīng)的x的值.