a and b are coefficients of x^{2} and x respectively.

c is a constant term.

**Example 1:**

Find the axis of symmetry of the graph of y = $x^{2}$−6x+5, using the formula.

**Solution:**

Given,

y = x^{2} – 6x + 5

For a quadratic function in standard form, y = a$x^{2}$+bx+c, the axis of symmetry is a vertical line, x = $\frac{-b}{2a}$

Here, a = 1, b = −6 and c = 5

Substituting the values of a and b,

x = -(-6)/2(1)

= 6/2

= 3

Therefore, the axis of symmetry is x = 3.

**Example 2:**

Find the axis of symmetry of the graph of y = 2x^{2} + 8x – 3, using the formula.

**Solution:**

Given,

y = 2x^{2} + 8x – 3

Comparing the given equation with the standard form y = ax^{2} + bx + c,

a = 2, b = 8, c = -3

And the axis of symmetry is a vertical line; x = -b/2a

Substituting the values of a and b,

x = -8/2(2)

= -8/4

= -2

Therefore, the axis of symmetry is x = -2.

**Example 3:**

If the axis of symmetry of the equation y = px^{2} – 12x – 5 is 2, then find the value of p.

**Solution:**

Given,

y = px^{2} – 12x – 5

Axis of symmetry is x = 2

For a quadratic function in standard form, y=a$x^{2}$+bx+c, the axis of symmetry is a vertical line, x = $\frac{-b}{2a}$

Here, a = p, b = -12, c = -5

According to the given,

-b/2a = 2

-(-12)/2p = 2

12 = 4p

12/4 = p

Therefore, p = 3