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Quadratic Equation Solutions Explained
Jan 25, 2025
Solving Quadratic Equations Using the Quadratic Formula
Introduction
The goal is to solve quadratic equations of the form ( ax^2 + bx + c = 0 ) using the quadratic formula.
Quadratic formula: [ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} ]
Example 1: Solving ( 2x^2 + 3x - 2 = 0 )
Identify coefficients:
( a = 2 )
( b = 3 )
( c = -2 )
Substitute into the quadratic formula:
( x = \frac{-3 \pm \sqrt{3^2 - 4 \cdot 2 \cdot (-2)}}{2 \cdot 2} )
Calculation steps:
( 3^2 = 9 )
( -4 \cdot 2 \cdot (-2) = 16 )
( 9 + 16 = 25 )
( \sqrt{25} = 5 )
Resulting expressions:
( x = \frac{-3 + 5}{4} ) and ( x = \frac{-3 - 5}{4} )
Simplify solutions:
( x = \frac{2}{4} = \frac{1}{2} )
( x = \frac{-8}{4} = -2 )
Solutions: ( x = \frac{1}{2} ) and ( x = -2 )
Verification:
Plug ( x = -2 ) back into the equation:
( 2(-2)^2 + 3(-2) - 2 = 0 ) verifies the solution.
Example 2: Solving ( 6x^2 - 17x + 12 = 0 )
Identify coefficients:
( a = 6 )
( b = -17 )
( c = 12 )
Substitute into the quadratic formula:
( x = \frac{-(-17) \pm \sqrt{(-17)^2 - 4 \cdot 6 \cdot 12}}{2 \cdot 6} )
Calculation steps:
( (-17)^2 = 289 )
( -4 \cdot 6 \cdot 12 = -288 )
( 289 - 288 = 1 )
( \sqrt{1} = 1 )
Resulting expressions:
( x = \frac{17 + 1}{12} ) and ( x = \frac{17 - 1}{12} )
Simplify solutions:
( x = \frac{18}{12} = \frac{3}{2} )
( x = \frac{16}{12} = \frac{4}{3} )
Solutions: ( x = \frac{3}{2} ) and ( x = \frac{4}{3} )
Conclusion
Successfully solved quadratic equations using the quadratic formula.
Verification of solutions ensures correctness.
Practice with different sets of quadratic equations to reinforce understanding.
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