In order to find the discriminant:
b^2-4ac
A= 1, B= 6, C=8
(6)^2-4(1)(8) = 4
Therefore, the equation has one real solution
First you connect the lines by making a triangle. Then you get the value of one side (4) and you square it. (4 squared= 16). You also do the same with another side (3 squared= 9). And then you add them and square root the number to get the answer. (5)