On this week, I learned about Interpreting the Discriminant. The interpreting the discriminant helps to find how many roots in equations.

– 4ac  It is called the discriminant of the quadratic equation.

The quadratic equation + bx +c = 0 has:

– 4ac > 0    It has two real roots.  Distinct root/real root

– 4ac = 0    It has one root.  Equal root

– 4ac <0   It has not root.    No root/ unreal root

Also there are rational root and irrational root. In – 4ac, if this number is perfect square number, it is rational number, but if it is not, it is irrational number.

self make questions) How many roots do this equation have?

+ 2x – 7 = 0    – 4(4)(-7) = 0     4+112 = 0   116 > 0    This equation has two real roots.

explain) At first to find the value of a, b, c. The value of a is 4, b is 2, and c is -7. And each number put in – 4ac = 0  Then 4+112=0   we find the value of this equation. 116 is bigger than zero. So 116 > 0 It has two real roots.

In this chapter, we have to understand how many roots in equation when -4ac is bigger than zero, less than zero, and equal with zero.