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fff" height="402" id="canvas_background" width="582" x="-1" y="-1"> <g display="none" height="100%" id="canvasGrid" overflow="visible" width="100%" x="0" y="0"> <rect fill="url(

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000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="281" xml:space="preserve" y="75.5">A</text> <text fill="

000000" fill-opacity="null" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_7" stroke="

000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="147" xml:space="preserve" y="307.5">B</text> <text fill="

000000" fill-opacity="null" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_8" stroke="

000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="418" xml:space="preserve" y="285.5">C</text> <path d="m182,264.5c4,1 4.29289,2.29291 5,3c0.70711,0.70709 1.07613,0.61731 2,1c1.30656,0.5412 1.1731,1.85272 2,3c1.30745,1.814 1.61731,3.07611 2,4c0.5412,1.30655 3.48625,1.82376 4,4c0.4595,1.9465 1.48625,2.82376 2,5c0.22975,0.97324 0,2 0,3l0,0" fill="none" fill-opacity="null" id="svg_9" stroke="

000" stroke-opacity="null" stroke-width="1.5"> <path d="m388,251.5c0,0 0,0 -1,0c-1,0 -2,1 -3,3c0,0 -0.77023,1.02675 -1,2c-0.51373,2.17624 -1,3 -1,4c0,1 -0.29291,1.29291 -1,2c-0.70709,0.70709 0,3 0,4c0,1 0,2 0,3c0,1 0,2 0,3c0,1 0,3 0,4c0,1 0,2 0,3c0,1 1,2 1,3l1,1" fill="none" fill-opacity="null" id="svg_10" stroke="

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000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="288" xml:space="preserve" y="308.5">D</text> <path d="m286,135.5c0,0 0.29291,1.29289 1,2c1.41422,1.41422 4.54916,2.95517 8,4c1.91418,0.57957 3.15225,0.76537 5,0c1.30655,-0.5412 2.186,-0.69255 4,-2c1.14728,-0.8269 2,-1 3,-2c1,-1 2,-1 3,-2l2,0l0,-1" fill="none" fill-opacity="null" id="svg_13" stroke="

000" stroke-opacity="null" stroke-width="1.5"> <path d="m259,133.5c2,0 2.82376,1.48625 5,2c0.97324,0.22975 2.02676,0.77025 3,1c2.17624,0.51375 2.69345,1.4588 4,2c0.92389,0.38269 2,0 3,1c0,0 1,0 2,0c1,0 2,-1 3,-1c1,0 2,-1 3,-1l1,0l0,-1" fill="none" fill-opacity="null" id="svg_14" stroke="

000" stroke-opacity="null" stroke-width="1.5"> <path d="m299,134.5c0,0 1.4588,0.69344 2,2c0.76538,1.84776 1,5 2,7l0,1" fill="none" fill-opacity="null" id="svg_15" stroke="

000" stroke-opacity="null" stroke-width="1.5"> <path d="m274,133.5c0,1 0,2 0,3c0,2 0,4 0,6l0,3l0,0" fill="none" fill-opacity="null" id="svg_16" stroke="

000" stroke-opacity="null" stroke-width="1.5"> <text fill="

000000" fill-opacity="null" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_17" stroke="

000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="264" xml:space="preserve" y="164.5">1</text> <text fill="

000000" fill-opacity="null" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_19" stroke="

000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="296" xml:space="preserve" y="161.5">2</text> </path></path></path></path></line></path></path></line></line></line></line></line> <rect fill="

fff" height="402" id="canvas_background" width="582" x="-1" y="-1"> <g display="none" height="100%" id="canvasGrid" overflow="visible" width="100%" x="0" y="0"> <rect fill="url(

gridpattern)" height="100%" stroke-width="0" width="100%" x="0" y="0"> </rect></g> </rect> <line fill="none" id="svg_1" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="305" x2="304" y1="42.5" y2="322.5"> <line fill="none" id="svg_6" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="147" x2="546" y1="173.5" y2="170.5"> <text fill="

000000" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_7" stroke="

000" stroke-width="0" text-anchor="start" x="197" xml:space="preserve" y="121.5">GT</text> <text fill="

000000" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_8" stroke="

000" stroke-width="0" text-anchor="start" x="193" xml:space="preserve" y="223.5">KL</text> <text fill="

000000" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_9" stroke="

000" stroke-width="0" text-anchor="start" x="319" xml:space="preserve" y="69.5">Cho</text> <line fill="none" id="svg_10" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="380" x2="393" y1="68.5" y2="44.5"> <line fill="none" id="svg_11" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="404" x2="394" y1="66.5" y2="45.5"> <line fill="none" id="svg_12" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="381" x2="406" y1="67.5" y2="66.5"> <text fill="

000000" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_14" stroke="

000" stroke-width="0" text-anchor="start" x="412" xml:space="preserve" y="62.5">ABC</text> <text fill="

000000" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_15" stroke="

000" stroke-width="0" text-anchor="start" x="315" xml:space="preserve" y="106.5">A</text> <polyline fill="none" id="svg_16" points="697,139.5 697,139.5 697,139.5 " stroke="

000" stroke-linecap="round" stroke-width="1.5"> <path d="m331,112.5c0,0 0.29291,-1.29289 1,-2c0.70709,-0.70711 1.82443,-1.09789 3,-3c0.52573,-0.85065 0.61731,-2.07612 1,-3c0.5412,-1.30656 1,-2 1,-2c1,-1 1,0 1,1c0,2 0,3 0,4c0,2 0,3 0,4c0,1 0,2 0,4l-1,1" fill="none" id="svg_17" stroke="

000" stroke-width="1.5"> <path d="m318,83.5c0,0 1.41885,-1.41886 3,-3c1.58115,-1.58114 4,-2 6,-3c0,0 0,1 0,2c0,1 1,1 1,2l0,1l1,1" fill="none" id="svg_18" stroke="

000" stroke-width="1.5"> <text fill="

000000" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_21" stroke="

000" stroke-width="0" text-anchor="start" x="343" xml:space="preserve" y="107.5">= A</text> <path d="m365,81.5c0,0 1.0535,0.4595 3,0c2.17624,-0.51374 2.69345,-1.4588 4,-2c0.92389,-0.38268 2,-1 3,-1c0,0 1,2 1,4l0,1l1,0" fill="none" id="svg_22" stroke="

000" stroke-width="1.5"> <path d="m386,102.5c2,0 3.29291,-0.70711 4,0c0.70709,0.70711 1.4588,0.69344 2,2c0.38269,0.92388 0,3 0,4c0,2 0.22977,3.02675 0,4c-0.51373,2.17625 -2,3 -5,5c0,0 -1.69345,-0.4588 -3,-1c-0.92389,-0.38268 -1.38269,-1.07612 -1,-2c0.5412,-1.30656 1.29291,-1.29289 2,-2c0.70709,-0.70711 1.07611,-1.38268 2,-1c1.30655,0.5412 2,2 2,2c1,1 1.69345,1.4588 3,2c0.92389,0.38268 2.07611,0.38268 3,0c1.30655,-0.5412 2,-1 2,-2l0,-1l0,0" fill="none" id="svg_23" stroke="

000" stroke-width="1.5"> <text fill="

000000" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_24" stroke="

000" stroke-width="0" text-anchor="start" x="316" xml:space="preserve" y="142.5">B = C</text> <line fill="none" id="svg_26" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="316" x2="324" y1="122.5" y2="115.5"> <line fill="none" id="svg_27" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="360" x2="368" y1="125.5" y2="116.5"> <line fill="none" id="svg_28" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="324" x2="332" y1="115.5" y2="120.5"> <line fill="none" id="svg_29" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="368" x2="374" y1="116.5" y2="123.5"> <line fill="none" id="svg_30" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-width="1.5" x1="646" x2="647" y1="186.5" y2="186.5"> <line fill="none" fill-opacity="null" id="svg_32" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-opacity="null" stroke-width="1.5" x1="325" x2="337" y1="223.5" y2="197.5"> <line fill="none" fill-opacity="null" id="svg_33" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-opacity="null" stroke-width="1.5" x1="348" x2="338" y1="222.5" y2="200.5"> <line fill="none" fill-opacity="null" id="svg_34" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-opacity="null" stroke-width="1.5" x1="324" x2="348" y1="223.5" y2="223.5"> <text fill="

000000" fill-opacity="null" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_37" stroke="

000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="355" xml:space="preserve" y="219.5">ADB =</text> <line fill="none" fill-opacity="null" id="svg_38" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-opacity="null" stroke-width="1.5" x1="719" x2="719" y1="231.5" y2="232.5"> <line fill="none" fill-opacity="null" id="svg_39" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-opacity="null" stroke-width="1.5" x1="429" x2="441" y1="224.5" y2="196.5"> <line fill="none" fill-opacity="null" id="svg_40" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-opacity="null" stroke-width="1.5" x1="459" x2="442" y1="224.5" y2="197.5"> <line fill="none" fill-opacity="null" id="svg_41" stroke="

000" stroke-linecap="undefined" stroke-linejoin="undefined" stroke-opacity="null" stroke-width="1.5" transform="rotate(-4.86657190322876 444.7099304199223,224.886978149414) " x1="430.08967" x2="459.3302" y1="224.88697" y2="224.88697"> <text fill="

000000" fill-opacity="null" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_42" stroke="

000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="467" xml:space="preserve" y="218.5">ADC</text> <text fill="

000000" fill-opacity="null" font-family="Helvetica, Arial, sans-serif" font-size="24" id="svg_43" stroke="

000" stroke-opacity="null" stroke-width="0" text-anchor="start" x="332" xml:space="preserve" y="254.5">AB = AC</text> </line></line></line></line></line></line></line></line></line></line></line></line></path></path></path></path></polyline></line></line></line></line></line>

1. Xét ΔABD và ΔADC :

1. Ta có : A^1 = A^2( GT)

AD : cạnh chung

B^ = C^ ( GT)

➩ΔADC = ΔADC (g.c.g)

2. Ta có :ΔADC = ΔADC (cmt)

⇒ AB = AC ( 2 cạnh tương ứng)

Chúc bạn học tốt !!!