Mathematics Grade 10 15 min

Solve a quadratic equation using the quadratic formula

Solve a quadratic equation using the quadratic formula

Tutorial Preview

1

Introduction & Learning Objectives

Learning Objectives Identify the coefficients a, b, and c from a quadratic equation in standard form. Recall and correctly write the quadratic formula from memory. Substitute the values of a, b, and c into the quadratic formula with correct signs and order of operations. Calculate the value of the discriminant (b² - 4ac) to determine the number of real solutions. Simplify the resulting expression to find the exact solutions for a quadratic equation. Solve quadratic equations that have two real solutions, one real solution, or no real solutions. Ever wondered how to calculate the exact path of a basketball for a perfect shot? 🏀 The quadratic formula gives us the power to predict trajectories! In this tutorial, you will learn how to use the quadratic formula, a powerful and...
2

Key Concepts & Vocabulary

TermDefinitionExample Quadratic EquationAn equation that can be written in the standard form ax² + bx + c = 0, where a, b, and c are constants and 'a' is not equal to zero. It is a second-degree polynomial equation.2x² + 5x - 3 = 0 is a quadratic equation. Standard FormThe form of a quadratic equation where all terms are on one side of the equals sign, set to zero, and arranged in descending order of their exponents.The equation 3x = 4 - x² written in standard form is x² + 3x - 4 = 0. CoefficientsThe numerical constants that multiply the variables in a polynomial. In ax² + bx + c = 0, 'a' is the quadratic coefficient, 'b' is the linear coefficient, and 'c' is the constant term.In the equation 5x² - x + 7 = 0, the coefficients are a = 5, b = -1, and...
3

Core Formulas

Standard Form of a Quadratic Equation ax^2 + bx + c = 0 Before applying the quadratic formula, you must arrange the equation into this form. This ensures you correctly identify the coefficients a, b, and c. The Quadratic Formula x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} This formula provides the solution(s) for x for any quadratic equation in standard form. The '±' symbol indicates that there may be two distinct solutions. The Discriminant and Nature of Roots \Delta = b^2 - 4ac If Δ > 0, there are two distinct real solutions. If Δ = 0, there is exactly one real solution (a repeated root). If Δ < 0, there are no real solutions.

5 more steps in this tutorial

Sign up free to access the complete tutorial with worked examples and practice.

Sign Up Free to Continue

Sample Practice Questions

Challenging
For what range of values of 'k' does the equation x² - 4x + k = 0 have no real solutions?
A.k > 4
B.k < 4
C.k > -4
D.k < -4
Challenging
The sum of the roots of a quadratic equation ax² + bx + c = 0 is given by -b/a, and the product is c/a. If the roots of an equation are x = \frac{5 + \sqrt{17}}{4} and x = \frac{5 - \sqrt{17}}{4}, what is the original equation?
A.2x² - 5x + 1 = 0
B.4x² - 10x + 17 = 0
C.x² - 5x + 2 = 0
D.2x² - 5x + 2 = 0
Challenging
A rectangular garden has an area of 84 m². The length is 2 meters longer than twice the width. If 'w' is the width, the equation is 2w² + 2w - 84 = 0. Use the quadratic formula to find the width of the garden.
A.7 m
B.6 m
C.-7 m
D.12 m

Want to practice and check your answers?

Sign up to access all questions with instant feedback, explanations, and progress tracking.

Start Practicing Free

More from Quadratic equations

Ready to find your learning gaps?

Take a free diagnostic test and get a personalized learning plan in minutes.