We evaluate b^2 - 4ac. If the answer is positive, then there are two real solutions. If it is zero, there is one real solution. If it is negative, there are 2 complex solutions. In this equation, a = 1, b = 5, c = 7. Now we plug in the numbers.
[tex] 5^{2}-4*1*7=1 [/tex]
Because this answer is positive, there are two real solutions.