First off, remember that finding the x-intercepts means setting y equal to zero and solving for the x-values, so this question is really asking you to "Solve 4x2 – 2x – 5 = 0".
Now, let's start the completing-the-square process. To begin, we have the original equation (or, if we had to solve first for "= 0", the "equals zero" form of the equation). In this case, we were asked for the x-intercepts of a quadratic function, which meant that we set the function equal to zero
Find the length of each of the four sides and add them all together. The short sides each measure 3 units and the long sides each measure 5 units. 3+3+ 5+5 = 16
