Question

Question #4d6f1

Answer 1

`x=-5`

Explanation:

Find the equation of the line of symmetry for the parabola

`y=x^2+10x+25`

The line of symmetry passes through the vertex of the parabola. The `x` coordinate of the vertex is found with the formula `x=-b/(2a)` for the equation of the form `y=ax^2+bx+c`.

In this example, `a=1`, `b=10` and `c=25`/

`x=-10/(2*1)=-5`

Because the line of symmetry passes through the vertex, the equation of the line is `x=-5`.

Check out the graph. The parabola is shown in red and the line of symmetry is shown in blue.