document.write( "Question 1164931: ABCD is rhombus. If ∠BAC = 40°, find ∠ADB and ∠ ABC. \n" ); document.write( "
Algebra.Com's Answer #789378 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "I won't do your for you.  I'll do one exactly like it.\r\n" );
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ABCD is rhombus. If ∠BAC = 36°, find ∠ADB and ∠ ABC.
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document.write( "∠ DAC = 36°   because the diagonals of a rhombus bisect each other.\r\n" );
document.write( "AC ⊥ BC       because the diagonals of a rhombus are perpendicular.\r\n" );
document.write( "ΔAED is a right triangle because two sides are perpendicular.\r\n" );
document.write( "∠ ADB = 54°   because the two angles of a right triangle are complementary.\r\n" );
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document.write( "AB ≅ AD       Sides of a rhombus are congruent\r\n" );
document.write( "ΔABD is isosceles   2 sides congruent\r\n" );
document.write( "∠ ABD = 54°   Base angles of isosceles triangle are congruent\r\n" );
document.write( "AB ≅ BC       Sides of a rhombus are congruent\r\n" );
document.write( "ΔABC is isosceles   2 sides congruent\r\n" );
document.write( "∠ BCA = 36°   Base angles of isosceles triangle are congruent\r\n" );
document.write( "∠BAC + ∠BCA + ∠ABC = 180°    Property of all triangles\r\n" );
document.write( "∠ABC = 180° - ∠BAC - ∠BCA  \r\n" );
document.write( "∠ABC = 180° - 36° - 36° = 108°\r\n" );
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document.write( "Now do yours the same way.\r\n" );
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document.write( "Edwin
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