Sign In
Set y equal to 0 and solve the equation with the Quadratic Formula.
Complete the square by adding half the coefficient to x.
Use the Zero Product Property to find the x-values of the x-intercepts.
(4,-6)
(4,-6)
(1.5,- 2.25)
To average the x-intercepts we first need to find them. At an x-intercept, the value of y is 0. Therefore, we will set y equal to 0 and solve the equation using the Quadratic Formula.
y= 0
Use the Quadratic Formula: a = 1, b= -8, c= 10
- (- a)=a
(- a)^2=a^2
Calculate power and product
Subtract term
Split into factors
sqrt(a* b)=sqrt(a)*sqrt(b)
Calculate root
Calculate quotient
State solutions
The line of symmetry is x_s=4 which is the x-value of the vertex. We can find the corresponding y-value by substituting 4 for x in the function and evaluating the right-hand side.
The vertex is (4,-6).
By completing the square, we can rewrite the equation in graphing form which allows us to identify the vertex directly from the equation.
Graphing Form:& y=a(x-h)^2+k
Vertex:& (h,k)
Complete the square
Calculate quotient
(- a)^2=a^2
Commutative Property of Addition
Split into factors
a^2-2ab+b^2=(a-b)^2
Calculate power
LHS-16=RHS-16
To identify the vertex, we have to rewrite the function so that it matches the graphing form exactly. Function:& y=(x-4)^2+(-6) Vertex:& (4,-6) The vertex of the quadratic function is (4,-6).
Let's use the method of averaging the x-intercepts. To find the x-intercepts, we will solve the equation when y=0. To do that, we factor out x and then use the Zero Product Property.
y= 0
Factor out x
Rearrange equation
Use the Zero Product Property
(II):LHS+3=RHS+3
The line of symmetry is x_s=1.5 which is the x-value of the vertex. We can find the corresponding y-value by substituting 1.5 for x in our equation.
The vertex of the function is located at (1.5,-2.25).