Question

Can someone help explain how to find the discriminants for these questions please?
4. What is the possible discriminant of the graph?
answers:
A) -13
B) zero
C) 16
D) 21
5.What is the possible discriminant of the graph?
answers:
A) -15
B) zero
C) 17
D) 25
I will show the graphs

Answer 1

4.

Answer 2

5.

Answer 3

the 1st graph is positive definite , that means the value of y is always positive no matter what value of x is input.

so how does this match to the discriminant

positive definite or negative definite parabola have a discriminant < 0

for a parabola that only touches the x-axis, doesn't cut the axis, these have a repeated root. So the discriminant = 0

where a curve cuts the x-axis twice these have a discriminant > 0

so hopefully this information allows you to match the curve to the discriminant value.

Answer 4

Thank you

Answer 5

is the discriminant > 0 and the value is a square number, then the x- intercepts are whole numbers.