Ian Y. answered 04/10/19
UCLA Grad, MBA and Math Instructor with over 15 years experience!
The three sides of a triangle should be proportional as either an acute, obtuse, or right triangle. This relationship is found by using a2 + b2 = c2. Since the problem says this is an obtuse triangle, a2 + b2 < c2, since one side is longer than the others. So you need to create an equation that relates x2 + (x-4)2 < 332 and solve it that way. This gives you 2x2-8x+16 < 1089, which then becomes 2x2-8x-1073 < 0, which you need to use the quadratic formula to solve. In simplest radical form the answer is: x = 2 +/- 1/2 * (square root (2162)). Hope it helps!!