document.write( "Question 177536: 4. A triangle has two unknown angles A and B. If A is three times the size of B, and C = 39° 40’ 32” , find the magnitudes of A and B. \n" ); document.write( "
Algebra.Com's Answer #132546 by gonzo(654)![]() ![]() ![]() You can put this solution on YOUR website! C = 39 degrees 40 minutes 32 seconds \n" ); document.write( "32 seconds = 32/60 minutes = 32/60/60 degrees \n" ); document.write( "40 minutes = 40/60 degrees \n" ); document.write( "add those two together to get: \n" ); document.write( "39.675555555..... degrees. \n" ); document.write( "sum of angles of a triangle is 180. \n" ); document.write( "180 - C = A + B = 180 - 39.6755555.... = 140.3244444...... degrees \n" ); document.write( "A is 3 * B, so A + B is the same as B + 3*B = 4*B = 140.3244444..... degrees \n" ); document.write( "this means that B = 140.324444...../4 = 35.0811111..... degrees \n" ); document.write( "this means that A = 3*B = 105.2433333..... degrees \n" ); document.write( "--- \n" ); document.write( "if we round to the nearest thousandth of a degree, we get: \n" ); document.write( "C = 39.676 degrees \n" ); document.write( "A = 105.243 degrees \n" ); document.write( "B = 35.081 degrees \n" ); document.write( "sum of 39.676 + 105.243 + 35.081 = 180 degrees. \n" ); document.write( "--- \n" ); document.write( "A is 3 * B means that 3* 35.081 = 105.243 means that 105.243 = 105.243 means that this statement (A = 3*B) is true. \n" ); document.write( "--- \n" ); document.write( "the magnitudes are in decimals. \n" ); document.write( "to convert back to degrees, minutes, and seconds, you need to convert the decimal portion to minutes and seconds. \n" ); document.write( "do this as follows: \n" ); document.write( "take the fractional part and multiply by 3600. \n" ); document.write( "this gets you seconds. \n" ); document.write( "divide those seconds by 60 to get minutes. \n" ); document.write( "that would be the integer part of the division. \n" ); document.write( "take the fractional part of the minutes and multiply by 60 to get the remaining seconds. \n" ); document.write( "--- \n" ); document.write( "to do this, use the unrounded answer, not the rounded answer, since the rounding will introduce some error in the result. \n" ); document.write( "example: \n" ); document.write( "C = 39.676 degrees \n" ); document.write( ".676 * 3600 = 2433.6 seconds \n" ); document.write( "2433.6 / 60 = 40.56 minutes \n" ); document.write( "number of minutes is 40 \n" ); document.write( "number of seconds is .56 * 60 = 33.6 = 34 seconds \n" ); document.write( "we know that the number of seconds is 32 because that was given. \n" ); document.write( "the rounding introduced the error. \n" ); document.write( "--- \n" ); document.write( "go back and do it again with the unrounded value this time. \n" ); document.write( "C = 39.675555555.... degrees \n" ); document.write( "use .675555555.... * 3600 to get seconds (maximum digits the calculator has should do). \n" ); document.write( "you get 2431.99999999.... seconds \n" ); document.write( "divide that by 60 to get: \n" ); document.write( "40.5333333...... minutes \n" ); document.write( "multiply .5333333..... * 60 to get: \n" ); document.write( "31.999999998 seconds \n" ); document.write( "your answer is: \n" ); document.write( "C = 39 degrees 40 minutes 32 seconds which agrees with the original value provided. \n" ); document.write( "--- \n" ); document.write( "do the same for A and B. \n" ); document.write( "--- \n" ); document.write( "A = 105.2433333..... degrees \n" ); document.write( ".2433333.... * 3600 = 875.99999999.... seconds \n" ); document.write( ".875.9999999.... / 60 = 14.6 minutes \n" ); document.write( ".6 * 60 = 36 seconds \n" ); document.write( "A = 105 degrees 14 minutes 36 seconds \n" ); document.write( "--- \n" ); document.write( "B = 35.0811111..... degrees \n" ); document.write( ".0811111.... * 3600 = 292 seconds \n" ); document.write( "292 / 60 = 4.866666666.... minutes \n" ); document.write( ".866666666... * 60 = 52 seconds \n" ); document.write( "B = 35 degrees 4 minutes 52 seconds \n" ); document.write( "--- \n" ); document.write( "you have: \n" ); document.write( "A = 105 degrees 14 minutes 36 seconds \n" ); document.write( "B = 35 degrees 4 minutes 52 seconds \n" ); document.write( "C = 39 degrees 40 minutes 32 seconds \n" ); document.write( "---- \n" ); document.write( "add these together to get: \n" ); document.write( "179 degrees 58 minutes 120 seconds \n" ); document.write( "this adds up to 180 degrees so the conversion from decimals to minutes and seconds is good. \n" ); document.write( "--- \n" ); document.write( "your answer is: \n" ); document.write( "A = 105 degrees 14 minutes 36 seconds \n" ); document.write( "B = 35 degrees 4 minutes 52 seconds \n" ); document.write( "---\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |