document.write( "Question 175945: BUILDING A SKI RAMP. WRITE AN EQUALITY IN THE VARIABLE X FOR THE DEGREE MEASURE OF THE SMALLEST ANGLE OF THE TRIANGLE, GIVEN THE DEGREE MEASURE OF THE SMALLEST ANGLE IS AT MOST 30 DEGREE. First ANGLE =X, Second ANGLE = X+8 \n" ); document.write( "
Algebra.Com's Answer #131061 by gonzo(654)![]() ![]() ![]() You can put this solution on YOUR website! let x be the smallest angle. \n" ); document.write( "let x + 8 be the second angle. \n" ); document.write( "let x + y = the third angle. \n" ); document.write( "----- \n" ); document.write( " \n" ); document.write( "this simplifies to \n" ); document.write( "this simplifies to \n" ); document.write( "where: \n" ); document.write( "x>0 \n" ); document.write( "x<=30 \n" ); document.write( "--- \n" ); document.write( "if x >0, then: \n" ); document.write( "(180-y-8)/2 > 0 \n" ); document.write( "multiply both sides of this equation by 2 to get: \n" ); document.write( "180 - y - 8 > 0 \n" ); document.write( "add y to both sides of the equation and combine like terms to get: \n" ); document.write( "172 > y \n" ); document.write( "subtract y from both sides of this equation and subtract 172 from both sides of this equation to get: \n" ); document.write( "-y > - 172 \n" ); document.write( "multiply both sides of this equation by -1 to get: \n" ); document.write( "y < 172 \n" ); document.write( "please note that multiplying both sides of an inequality by a minus number changes the inequality. \n" ); document.write( "--- \n" ); document.write( "so we know that y has to be smaller than 172. \n" ); document.write( "--- \n" ); document.write( "if x <= 30, then: \n" ); document.write( "(180-y-8)/2 <= 30 \n" ); document.write( "multiply both sides by 2 to get: \n" ); document.write( "180 - y - 8 <= 60 \n" ); document.write( "add y to both sides and subtract 60 from both sides to get: \n" ); document.write( "180 - 60 - 8 <= y \n" ); document.write( "combine like terms to get: \n" ); document.write( "112 <= y \n" ); document.write( "subtract 112 from both sides of the equation and subtract y from both sides of the equation to get: \n" ); document.write( "-y <= -112 \n" ); document.write( "multiply both sides of the equation by -1 to get: \n" ); document.write( "y >= 112 \n" ); document.write( "--- \n" ); document.write( "looks like x will be in the range of: \n" ); document.write( "0 < x <= 30 \n" ); document.write( "when y is in the range of: \n" ); document.write( "112 <= y < 172 \n" ); document.write( "---\r \n" ); document.write( "\n" ); document.write( "to prove this is true, take several values of y in and out of the acceptable range and see what happens to x. \n" ); document.write( "--- \n" ); document.write( "when y = 172, x = 0. \n" ); document.write( "since y is outside of the acceptable range, x is also outside of the acceptable range so this is good. \n" ); document.write( "--- \n" ); document.write( "when y = 112, x = 30. \n" ); document.write( "since y is within the acceptable range, x is also within the acceptable range so this is good. \n" ); document.write( "--- \n" ); document.write( "when y = 150, x = 11. \n" ); document.write( "since y is within the acceptable range, x is also within the acceptable range so this is good. \n" ); document.write( "--- \n" ); document.write( "when y = 200, x = -14. \n" ); document.write( "since y is outside of the acceptable range, x is also outside of the acceptable range so this is good. \n" ); document.write( "--- \n" ); document.write( "when y = 110, x = 31. \n" ); document.write( "since y is outside of the acceptable range, x is also outside of the acceptable range so this is good. \n" ); document.write( "--- \n" ); document.write( "the limits for y lead to the proper limits for x so the answer is good. \n" ); document.write( "the equation to solve this problem is: \n" ); document.write( " \n" ); document.write( "the requirements for x are: \n" ); document.write( "0 < x <= 30 \n" ); document.write( "the requirements for y in order to satisfy the requirements for x are: \n" ); document.write( "112 <= y < 172 \n" ); document.write( "--- \n" ); document.write( "as long as y is in the acceptable range, x will be in the acceptable range. \n" ); document.write( "as long as y is outside of the acceptable range, x will be outside of the acceptable range. \n" ); document.write( "--- \n" ); document.write( "since they asked for the equality equation for the smallest angle, your answer has to be: \n" ); document.write( " \n" ); document.write( "with the stipulation that: \n" ); document.write( "112 <= y < 172 \n" ); document.write( "--- \n" ); document.write( "i don't think you can solve this problem without introducing another variable since the range of that variable is important to the solution. \n" ); document.write( "--- \n" ); document.write( "if you had stipulated what the third angle had to be in terms of x, that would have been different. \n" ); document.write( "then we would have had a value for y and we could have used that value in place of y. \n" ); document.write( "---\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |