25.如圖,在正方形ABCD中,E為AB的中點(diǎn),以A為原點(diǎn),AB、AD所在直線為x軸、y軸,建立平面直角坐標(biāo)系.正方形ABCD的邊長(zhǎng)是方程x
2-8x+16=0的根.點(diǎn)P從點(diǎn)B出發(fā),沿BC-CD向點(diǎn)D運(yùn)動(dòng),同時(shí)點(diǎn)Q從點(diǎn)E出發(fā),沿EB-BC向點(diǎn)C運(yùn)動(dòng),點(diǎn)P的速度是每秒2個(gè)單位長(zhǎng)度,點(diǎn)Q的速度是每秒1個(gè)單位長(zhǎng)度.當(dāng)點(diǎn)P運(yùn)動(dòng)到點(diǎn)D時(shí),P、Q兩點(diǎn)同時(shí)停止運(yùn)動(dòng).設(shè)點(diǎn)P運(yùn)動(dòng)的時(shí)間為t秒,△APQ的面積為S.
(1)求點(diǎn)C的坐標(biāo);
(2)求S關(guān)于t的函數(shù)關(guān)系式;
(3)當(dāng)△AQP是以AP為底邊的等腰三角形時(shí),直接寫出點(diǎn)P的坐標(biāo).