来自贾利民的问题
已知,如图△ABC与△ADE中,D在BC上,∠1=∠2=∠3(1)求证:△ABC∽△ADE;(2)若AB=4,AD=2,AC=3,求AE的长.
已知,如图△ABC与△ADE中,D在BC上,∠1=∠2=∠3
(1)求证:△ABC∽△ADE;
(2)若AB=4,AD=2,AC=3,求AE的长.
1回答
2020-12-25 05:39
已知,如图△ABC与△ADE中,D在BC上,∠1=∠2=∠3(1)求证:△ABC∽△ADE;(2)若AB=4,AD=2,AC=3,求AE的长.
已知,如图△ABC与△ADE中,D在BC上,∠1=∠2=∠3
(1)求证:△ABC∽△ADE;
(2)若AB=4,AD=2,AC=3,求AE的长.
(1)证明:∵△ABC与△ADE中,D在BC上,∠2=∠3,∴∠E=∠C,∵∠DAE=∠DAC+∠2,∠BAC=∠DAC+∠1,∵∠1=∠2,∴∠DAE=∠BAC,∵∠1=∠3,∴∠B=∠ADE,∴△ABC∽△ADE;(2)∵△ABC∽△ADE(已证);∴ABAD=AEAC...