 Related Topics:
Algebra Word Problems
Common Core (Algebra)
Common Core for Mathematics

Examples, solutions, videos, and lessons to help High School students learn how to solve quadratic equations by inspection (e.g., for x2 = 49), taking square roots, completing the square, the quadratic formula and factoring, as appropriate to the initial form of the equation. Recognize when the quadratic formula gives complex solutions and write them as a ± bi for real numbers a and b.

### Suggested Learning Targets

• Solve quadratic equations in one variable by simple inspection, taking the square root, factoring, and completing the square.
• Understand why taking the square root of both sides of an equation yields two solutions.
• Use the quadratic formula to solve any quadratic equation, recognizing when  the formula produces complex solutions. Write the solutions in the form a Ңi , where a and b are real numbers.
• Explain how complex solutions affect the graph of a quadratic equation.
Common Core: HSA-REI.B.4b

Solve a quadratic equation using inspection - A-REI.4
In this lesson, you will learn how to solve a quadratic equation by inspection. Solve a quadratic by taking a square root - A-REI.4
In this lesson, you will learn how to solve a quadratic equation by taking a square root.

Solve a quadratic equation by factoring - A-REI.4
In this lesson, you will learn how to solve a quadratic equation by looking at the factored form of the equation. Solve a quadratic equation by completing the square - A-REI.4
In this lesson, you will learn how to solve a quadratic equation by completing the square. Solve a quadratic equation using the quadratic formula - A-REI.4
In this lesson, you will learn how to solve a quadratic equation using the quadratic formula. Determine the nature of the roots of a quadratic equation - A-REI.4
In this lesson, you will learn how to tell the nature of the roots of a quadratic by looking at the discriminant.

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