Answer :
Answer: x=1
Step-by-step explanation:
Step 1: Graph using your calculator
Step 2: X=1 is where both sides of the line is equal
Answer: x = 1
Explanation
The equation given by your teacher is of the form
y = ax^2+bx+c
In this case,
- a = 1
- b = -2
- c = -8
The line of symmetry is found by this formula: h = -b/(2a)
Let's plug in the given values to find the following
h = -b/(2a)
h = -(-2)/(2*1)
h = 1
This is the x coordinate of the vertex located at (h,k).
It leads to the line of symmetry x = 1. This is the vertical mirror line splitting the parabola in equal halves. Notice how the value of c does not affect the answer. Why not? Because c only shifts the parabola up or down, which means we're moving along the same vertical line.
See the graph below. I used GeoGebra to make it, but you can use another tool like Desmos or similar.
