Answer: x = -2
Step-by-step explanation: I would first convert the equation to factored form.
In factored form or intercept form, we can see the intercepts right away.
To do this, we set up two sets of parenthses.
First off, x² breaks down as x and x so we
use those factors as the first position.
Then look for factors of the constant term that add to 4.
So factors of -5 that add to 4.
These factors are +5 and -1.
So we have (x + 5)(x - 1).
So we have y = (x + 5)(x - 1).
Now we can see that our zeros (x-intercepts) are -5 and +1.
Remember, to find zeros, substitute a 0 in for y.
Now to find the axis of symmetry or the fold line that splits
our parabola down the middle, we average the zeros.
To do this, add the zeros and multiply by 1/2.
So -5 + 1 is -4 and -4(1/2) is -2.
So the equation for axis of symmetry is x = -2.
