Puas yog cov kaum sab xis ntawm lub isosceles trapezoid congruent?
Puas yog cov kaum sab xis ntawm lub isosceles trapezoid congruent?

Video: Puas yog cov kaum sab xis ntawm lub isosceles trapezoid congruent?

Video: Puas yog cov kaum sab xis ntawm lub isosceles trapezoid congruent?
Video: Puas yog luag dag koj xwb | Kawm muas 2024, Kaum ib hlis
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Base (sab saum toj thiab hauv qab) ntawm ib isosceles trapezoid yog thaum uas tig mus. Sab nraud ntawm ib qho isosceles trapezoid yog tib qhov ntev ( kev sib haum xeeb ). Cov lub kaum sab xis ntawm ob sab ntawm lub hauv paus yog tib qhov loj / ntsuas ( kev sib haum xeeb ).

Ib yam li ntawd, cov kaum sab xis ntawm daim duab peb sab isosceles puas sib haum?

Cov Lub kaum sab xis ntawm daim duab peb sab isosceles yog cov lub kaum sab xis tsim los ntawm cov puag thiab ib ceg ntawm lub daim duab peb sab . Cov puag cov ces kaum theorem converse hais tias yog ob lub kaum sab xis hauv a daim duab peb sab yog kev sib haum xeeb , ces ob sab opposite cov lub kaum sab xis kuj yog kev sib haum xeeb.

Tom qab, lo lus nug yog, dab tsi yog lub hauv paus kaum ntawm lub trapezoid? Ib khub ntawm lub kaum sab xis uas share tib yam puag hu ua puag cov ces kaum ntawm trapezoid . Hauv daim duab 1, ∠ A thiab ∠ B lossis ∠ C thiab ∠ D yog puag cov ces kaum ntawm trapezoid ABCD. Ob qhov tshwj xeeb ntawm cov isosceles trapezoid tuaj yeem ua pov thawj. Txoj Cai 53: Cov kaum sab xis ntawm ib qho isosceles trapezoid sib npaug.

Tib neeg kuj nug, dab tsi yog lub hauv paus kaum ntawm lub isosceles trapezoid?

Cov puag cov ces kaum ( lub kaum sab xis tsim ntawm cov uas tsis yog-parallel sab thiab parallel sab) yog sib npaug hauv ib isosceles trapezoid . Diagonals ntawm ib isosceles trapezoid yog sib npaug ntawm qhov ntev. Qhov sum ntawm opposite lub kaum sab xis hauv ib isosceles trapezoid yog 180 degrees.

Puas yog ob txhais ceg ntawm lub trapezoid sib haum?

THEOREM: Yog hais tias ib tug plaub fab (nrog ib txheej ntawm parallel sab) yog ib qho isosceles trapezoid , nws ob txhais ceg yog kev sib haum xeeb . THEOREM: (converse) Yog a trapezoid muaj sib ceg ceg , nws yog isosceles trapezoid.

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