Solve Quadratic Equations Using the Quadratic Formula: example 10.29

Solve $x^{2} - 6 x + 5 = 0$ by using the Quadratic Formula.

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

Solve $a^{2} - 2 a - 15 = 0$ by using the Quadratic Formula.

How did it go?


This equation is in standard form.
Identify the a, b, c values.
Write the Quadratic Formula.
Then substitute in the values of a, b, c.
Simplify.
Rewrite to show two solutions.
Simplify.
Check.


This equation is in standard form.
Identify the a, b, c values.
Write the Quadratic Formula.
Then substitute in the values of a, b, c.
Simplify.
Rewrite to show two solutions.
Simplify.
Check.