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The Quadratic Formula. What does t he Quadratic Formula Do ?. The Quadratic formula allows you to find the roots of a quadratic equation (if they exist) even if the quadratic equation does not factorize . The formula states that for a quadratic equation of the form :.
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What does the Quadratic Formula Do ? The Quadratic formula allows you to find the roots of a quadratic equation (if they exist) even if the quadratic equation does not factorize. The formula states that for a quadratic equation of the form : ax2 + bx + c = 0 The roots of the quadratic equation are given by :
Example 1 Use the quadratic formula to solve the equation : x 2 + 5x + 6= 0 Solution: Given: x 2 + 5x + 6= 0 Where a = 1 b = 5 c = 6 and then, substituting gives x = - 2 or x = - 3 These are the roots of the original equation.
Example 2 Use the quadratic formula to solve the equation: 8x 2 + 2x - 3= 0 Solution: Given: 8x 2 + 2x - 3= 0 Where a = 8 b = 2 c = -3 and then, substituting gives x = ½ or x = - ¾ These are the roots of the original equation..
Example 3 Use the quadratic formula to solve the equation:8x 2 - 22x + 15= 0 Solution: Given: 8x 2 - 22x + 15= 0 Where a = 8 b = -22 c = 15 and then, substituting gives x = 3/2 or x = 5/4 These are the roots of the original equation.
Example 4 Use the quadratic formula to solve for x to 2 decimal places: 2x 2 +3x - 7= 0 Solution: Given: 2x 2 + 3x – 7 = 0 Where a = 2 b = 3 c = - 7 and then, substituting gives x = 1.27 or x = - 2.77 These are the roots of the original equation.