document.write( "Question 231164: The terminal side of angle theta in standard position lies on the given line in the given quadrant. Find sin theta, cos theta and tan theta.\r
\n" ); document.write( "\n" ); document.write( "2x + 3y=0; quadrant IV \n" ); document.write( "
Algebra.Com's Answer #171138 by jsmallt9(3758)\"\" \"About 
You can put this solution on YOUR website!
In the fourth quadrant, x's are positive and y's are negative. So let's find a point on the line in the fourth quadrant by picking a positive value for x and the using the equation to find the corresponding y. To avoid fractions, I'm going to pick 3 for x:
\n" ); document.write( "2(3) + 3y = 0
\n" ); document.write( "6 + 3y = 0
\n" ); document.write( "3y = -6
\n" ); document.write( "y = -2
\n" ); document.write( "Here's a drawing of what we have so far:
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\n" ); document.write( "We already have what we need for tan. But we need the hypotenuse for the sin and cos. We'll use the Pythagorean Theorem for this:
\n" ); document.write( "\"3%5E2+%2B+2%5E2+=+h%5E2\"
\n" ); document.write( "\"9+%2B+4+=+h%5E2\"
\n" ); document.write( "\"13+=+h%5E2\"
\n" ); document.write( "\"sqrt%2813%29+=+h\"
\n" ); document.write( "Now we can find our values. (Since Algebra.com's formula software does not \"do\" theta, for some unknown reason, I'll use x instead):
\n" ); document.write( "\"sin%28x%29+=+%28-2%29%2Fsqrt%2813%29\"
\n" ); document.write( "\"cos%28x%29+=+3%2Fsqrt%2813%29\"
\n" ); document.write( "\"tan%28x%29+=+%28-2%29%2F3\"
\n" ); document.write( "We don't usually leave square roots in denominators so we'll rationalize the sin and cos:
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