已知梯形上下底和坡比系数,怎样求高度 已知梯形上底2,下底6,坡比系数1:2,求梯形高度
\u5df2\u77e5\u68af\u5f62\u7684\u4e0b\u5e95\uff0c\u9ad8\uff0c\u548c\u5761\u6bd4\uff0c\u600e\u6837\u8ba1\u7b97\u4e0a\u5e95\u901a\u8fc7\u5761\u6bd4\u4e0e\u9ad8\uff0c\u5229\u7528\u4e09\u89d2\u51fd\u6570\uff0c
\u53ef\u6c42BE\u4e0eCF\uff0c
\u4e0a\u5e95AD=\u4e0b\u5e95BC-(BE+CF)\u3002
\u6839\u636e\u9898\u610f\u5f97\u5982\u56fe\uff1a\u2220A=\u2220D=90\u00b0\uff0cCD=2\uff0cAB=6\uff0c
\u8fc7C\u4f5cCE\u22a5AB\u4e8eE\uff0c\u5219\u56db\u8fb9\u5f62AECD\u662f\u77e9\u5f62\uff0c
\u2234AE=CD=2\uff0c\u2234BE=AB-AE=4\uff0c
\u5761\u6bd4CE\uff1aBE=1\uff1a2\uff0c
\u2234CE=2\uff0c
\u5373\u9ad8\u4e3a2\u3002
h=1
绛旓細h/(6-2)/2=1:2 h=1
绛旓細姊舰鐨勪笅搴=涓婂簳+l+l鈥
绛旓細鍥炵瓟锛氫緷棰樻剰,姹俠,宸茬煡h=2.5 a=0.2 鍧℃瘮=h/L=1/0.3,甯﹀叆h=2.5,鍙互寰桳=2.5*0.3/1=0.75,鑰宐=a+L,甯﹀叆a鍜孡鐨勫煎緱鍒癰=0.75+0.2=0.95
绛旓細鍧℃瘮CE锛欱E=1锛2锛屸埓CE=2锛屽嵆楂樹负2銆
绛旓細棰囨瘮鐨勮瘽涓鑸兘鏄潯鐨勫瀭鐩翠笅鏉ワ紝鎶曞奖鍦ㄤ笅搴曚笂闈㈢殑閭d釜闀垮害闄や互鍧°傞偅涔堜綘鍙渶瑕鐭ラ亾銆傞偅涓姇褰卞闀匡紝鑰屾姇褰辨槸绛変簬涓嬪簳鍑忎笂搴曠殑銆備綘灏卞彲浠ュ垪鏂圭▼寮忋傚垎鍒眰鍑轰粬浠殑鐮寸唤銆
绛旓細鐢遍鎰忓彲鐢诲嚭涓嬪浘锛屽垯2.51/x=0.2 x=12.55 鎵浠ヤ笅搴=涓婂簳+12.55=6+12.55=18.55
绛旓細浠庝笂搴曠殑涓ら《鐐瑰悜涓嬪仛鍨傜嚎锛屼袱杈规槸涓や釜鍏ㄧ瓑鐨勭洿瑙掍笁瑙掑舰 鍧″害灏辨槸搴曡鐨勬鍒囧硷紝鏍规嵁楂樺拰鍧″害鍙互璁$畻閭d袱涓洿瑙掍笁瑙掑舰鐨勫簳 涓嬪簳=涓婂簳鍔犱笂杩欎袱娈 0.74脳1.5脳2+26=28.2
绛旓細涓婂簳x 锛屾尝姣旓細a=h/锛坉-x锛変唬鍏ユ暟鍊兼尝姣攁銆傞珮搴锛屼笅搴昫 锛涜В鍑烘潵寰楀埌 x=d-h/a
绛旓細杩欎釜棰樼洰涓凡缁忓憡璇夋垜浠笅搴曚负1.6绫充簡銆傚鏋滄槸姹傛褰㈢殑楂橈紝閭f潯浠朵笉澶熴傚鏋滄槸绛夎叞姊舰锛閭i珮=(1.6-0.5)梅2梅0.4=1.375锛屽鏋滄槸鐩磋姊舰锛岄偅闈炵洿瑙鍧℃瘮涓1锛0.4鐨勬潯浠朵笅锛岄珮=(1.6-0.5)梅0.4=2.75
绛旓細棣栧厛鍧℃瘮灏辨槸鍧¢潰鍨傜洿楂樺害姣涓婁笅搴曞拰涓婂簳宸紝鍗1锛1.5锛4.4锛氾紙涓嬪簳锛嶄笂搴曪級锛岃繖鏍峰彲浠ヨВ鍑轰笅搴曚笌涓婂簳涔嬪樊鏄6.6锛屼笂搴曟槸0.1锛岃姊舰闈㈢Н灏辨槸锛堜笂搴曪紜涓嬪簳锛/2脳楂樺害锛濓紙0.1+6.7锛/2脳4.4锛14.69m²銆