Write the quadratic formula.

x = (-b ± √(b² - 4ac)) / 2a

In the quadratic formula, what does the '±' symbol indicate?

It indicates there are two possible solutions: one with addition and one with subtraction.

Grade 9th Grade · Math · 45 min· Esl

I can use the quadratic formula to find the solutions of quadratic equations.

Khan Academy · 5:34

Example 1: Using the quadratic formula | Quadratic equations | Algebra I | Khan Academy

3 key concepts

1
The quadratic formula can be used to solve equations in the form 0 = ax² + bx + c, where a, b, and c are coefficients.
2
The quadratic formula states that x = -b ± √(b² - 4ac) / 2a, giving two possible solutions for x.
3
In the example, a = -7, b = 2, and c = 9, which are substituted into the quadratic formula to find the solutions for q.

10 questions · Multiple choice & Short answer

Quick comprehension check

“Use the quadratic formula to solve for x: 0 = 3x² + 5x - 2. Show all steps.”

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