Shnol D.Z.
In quadrilaterals \$ABCD\$ and \$A_1B_1C_1D_1\$, the corresponding angles are equal. In addition, \$AB=A_1B_1\$, \$AC=A_1C_1\$, \$BD=B_1D_1\$. Are the quadrilaterals \$ABCD\$ and \$A_1B_1C_1D_1\$ necessarily equal?
Solution
Let \$A=A_1\$, \$B=B_1\$, \$ on side \$ and , \$ \$AC=AC_1=BD=BD_1\$ and isosceles trapezoids \$ABCD\$, \$A_1B_1C_1D_1\$ satisfy all conditions, but are not equal.
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## Answer
No.
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