document.write( "Question 381169: in right triangle DEF, angle D eguals 90 and angle F is 12 degrees less than twice angle E. find angle E \n" ); document.write( "

Algebra.Com's Answer #270404 by neatmath(302) $\"\"$ $\"About$

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The sum of the three measures of a triangle is ALWAYS 180.
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\n" ); document.write( "\n" ); document.write( "So, we know that D+E+F=180
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\n" ); document.write( "\n" ); document.write( "D=90, so we know that 90+E+F=180 thus
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\n" ); document.write( "\n" ); document.write( "E+F=90
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\n" ); document.write( "\n" ); document.write( "Also, we are given
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\n" ); document.write( "\n" ); document.write( "F+12=2*E
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\n" ); document.write( "\n" ); document.write( "F+12=2E
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\n" ); document.write( "\n" ); document.write( "F=2E-12
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\n" ); document.write( "\n" ); document.write( "Therefore, substituting for F back into E+F=90 gives us
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\n" ); document.write( "\n" ); document.write( "E+(2E-12)=90
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\n" ); document.write( "\n" ); document.write( "3E-12=90
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\n" ); document.write( "\n" ); document.write( "3E=102
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\n" ); document.write( "\n" ); document.write( "E=34
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\n" ); document.write( "\n" ); document.write( "So angle E is 34 degrees, which is the answer.
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\n" ); document.write( "\n" ); document.write( "In additon, since we know that E+F=90 then we have
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\n" ); document.write( "\n" ); document.write( "34+F=90
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\n" ); document.write( "\n" ); document.write( "F=56
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\n" ); document.write( "\n" ); document.write( "I hope this helps!
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