Solving Quadratic Equations Using the Quadratic
Formula
Example
Solve using the quadratic formula: 10 - 5x2 = 6x
Solution
Step 1 Write the quadratic equation in standard form,
ax2 + bx + c = 0.
Subtract 6x from both sides of the equation.
On the left side, write the terms in
decreasing powers of x.
Step 2 Identify the values of a, b, and c. |
10-5x2 = 6x
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Step 3 Substitute the values of a,
b, and c into the quadratic
formula. |
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Step 4 Simplify. |
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Simplify the radical.
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Factor -2 from the numerator
and denominator.
Reduce by canceling the
common factor, -2
Step 5 Check each solution.
We leave the check to you. |
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The two solutions of 10 - 5x2 = 6x are
Note:
Here’s another way to simplify: |
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Factor out 2. |
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Multiply by
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(We multiplied by
because we do not
want a negative sign in the denominator.)
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