document.write( "Question 124499: A square of side length 10cm is inscribed in a circle. Calculate the diameter of the circle \n" ); document.write( "
Algebra.Com's Answer #91244 by bucky(2189) ![]() You can put this solution on YOUR website! It might help you to visualize this problem if you made a rough sketch of it. Draw a circle and \n" ); document.write( "then, on the inside of the circle draw a square that has each of its corners on the circle. \n" ); document.write( ". \n" ); document.write( "Once you do that, draw a diagonal line that connects one corner of the square with the other \n" ); document.write( "corner on the opposite side. This diagonal line will be a diameter of the circle. \n" ); document.write( ". \n" ); document.write( "Notice that this diagonal line also divides the square into two right triangles. You can see \n" ); document.write( "that the two legs of each triangle are sides of the square. Therefore, each leg is 10 cm in length. \n" ); document.write( "You then need to find the hypotenuse (long side) of the triangle and when you do, you will have \n" ); document.write( "the length of the diameter of the circle. \n" ); document.write( ". \n" ); document.write( "You can find the length of the hypotenuse by applying the Pythagorean theorem which says that \n" ); document.write( "the sum of the squares of the two legs of a right triangle is equal to the square of the \n" ); document.write( "hypotenuse. In equation form this is: \n" ); document.write( ". \n" ); document.write( "A^2 + B^2 = C^2 \n" ); document.write( ". \n" ); document.write( "where A and B are the two legs and C is the hypotenuse. \n" ); document.write( ". \n" ); document.write( "For this problem, A and B are both 10 cm. So, substituting 10 for A and 10 for B makes the \n" ); document.write( "equation: \n" ); document.write( ". \n" ); document.write( "10^2 + 10^2 = C^2 \n" ); document.write( ". \n" ); document.write( "and since 10^2 is equal to 100 you can reduce the equation to: \n" ); document.write( ". \n" ); document.write( "100 + 100 = C^2 \n" ); document.write( ". \n" ); document.write( "Add the two numbers on the left side and you have: \n" ); document.write( ". \n" ); document.write( "200 = C^2 \n" ); document.write( ". \n" ); document.write( "You can solve for C by taking the square root of both sides to get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Just to get this in a conventional form, let's reverse the sides of the equation to get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "But 200 can be replaced by 100*2 to get: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "and by the rules of square roots this becomes: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "and since the square root of 100 is 10, this further reduces to: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "The units being used are cm, so the answer is that C, the diagonal of the \n" ); document.write( "circle, is: \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( ". \n" ); document.write( "Hope this helps you to understand the problem a little better. \n" ); document.write( ". \n" ); document.write( " \n" ); document.write( " |