document.write( "Question 214848This question is from textbook Geometry for Enjoyment and Challenge
\n" ); document.write( ": i'm having trouble finding m<1 . . .\r
\n" ); document.write( "\n" ); document.write( "Given:
\n" ); document.write( "<1 and <2 are supplementary
\n" ); document.write( "<2 and <3 are supplementary
\n" ); document.write( "<1= x^2+3y
\n" ); document.write( "<2= 20y+3
\n" ); document.write( "<3= 3y+4x\r
\n" ); document.write( "\n" ); document.write( "Find: m<1
\n" ); document.write( "(does not require proof)\r
\n" ); document.write( "\n" ); document.write( "i've found x= -5.75+44.25, but i am confused on how to proceed ? how would you solve (-5.75+44.25)^2+3y+20y+3=180 ?
\n" ); document.write( "please help, thank you !!
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Algebra.Com's Answer #162314 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
Using the fact that the sum of supplementary angles is 180 degrees, we can write two equations in x and y:
\n" ); document.write( "\"A%5B1%5D%2BA%5B2%5D+=+180\" Substitute:
\n" ); document.write( "\"A%5B1%5D+=+x%5E2%2B3y\"
\n" ); document.write( "\"A%5B2%5D+=+20y%2B3\" we get:
\n" ); document.write( "1). \"%28x%5E2%2B3y%29%2B%2820y%2B3%29+=+180\" Similarly for angles 2 and 3.
\n" ); document.write( "\"A%5B2%5D+=+20y%2B3\"
\n" ); document.write( "\"A%5B3%5D+=+3y%2B4x\" Add the angles.
\n" ); document.write( "2). \"%2820y%2B3%29%2B%283y%2B4x%29+=+180\" Simplifying 1). and 2). we have:
\n" ); document.write( "1a). \"x%5E2%2B23y%2B3+=+180\"
\n" ); document.write( "2a). \"4x%2B23y%2B3+=+180\" Subtracting 2a) from 1a) we get:
\n" ); document.write( "3). \"x%5E2-4x+=+0\" Factor an x.
\n" ); document.write( "3a). \"x%28x-4%29+=+0\" so that:
\n" ); document.write( "\"x+=+0\" or \"x+=+4\" Substitute x = 0 into equation 1a) and solve for y.
\n" ); document.write( "\"0%5E2%2B23y%2B3+=+180\"
\n" ); document.write( "\"23y+=+177\"
\n" ); document.write( "\"y+=+7.6957\" or substitute x = 4 into equation 1a) and solve for y.
\n" ); document.write( "\"%284%29%5E2%2B23y%2B3+=+180\"
\n" ); document.write( "\"19%2B23y+=+180\" Subtract 19 from both sides.
\n" ); document.write( "\"23y+=+161\" Divide both sides by 23.
\n" ); document.write( "\"y+=+7\"
\n" ); document.write( "So angle 1 can have one of two measures:
\n" ); document.write( "\"A%5B1%5D+=+x%5E2%2B3y\" Substitute x = 0 and y = 7.6957
\n" ); document.write( "\"A%5B1%5D+=+0%2B3%287.6957%29\"
\n" ); document.write( "\"highlight_green%28A%5B1%5D+=+23.0871%29\"degrees.
\n" ); document.write( "\"A%5B2%5D+=+20y%2B3\"
\n" ); document.write( "\"A%5B2%5D+=+20%287.6957%29%2B3\"
\n" ); document.write( "\"highlight_green%28A%5B2%5D+=+156.914%29\"degrees.
\n" ); document.write( "or...
\n" ); document.write( "\"A%5B1%5D+=+x%5E2%2B3y\" x=4 and y = 7.
\n" ); document.write( "\"A%5B1%5D+=+4%5E2%2B3%287%29\"
\n" ); document.write( "\"A%5B1%5D+=+16%2B21\"
\n" ); document.write( "\"highlight%28A%5B1%5D+=+37%29\"degrees.
\n" ); document.write( "\"A%5B2%5D+=+20y%2B3\"
\n" ); document.write( "\"A%5B2%5D+=+20%287%29%2B3\"
\n" ); document.write( "\"highlight%28A%5B2%5D+=+143%29\" degrees.
\n" ); document.write( "As you can see, in both cases, the sums of angle 1 and angle 2 are 180 degrees.
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