How do you solve the quadratic #3x^2-2x=2x+7# using any method?
2 Answers
Explanation:
Given:
Subtract
7 is a prime number so does not share any common factors other than 1 with the other coefficients.
Compare to the standardised equations:
Where
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Same solution but using completing the square. The process introduces an error that has to be corrected by the inclusion of
Takes longer to explain than do the maths.
Explanation:
Given:
Write as:
Let the constant of correction be
At this point
Write as:
Take the square from
Halve the coefficient of
Now get rid of the
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We now have to find the value of
The error comes from the term
Equation(1)
Equation(2)
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So from equation(2) we have
So equation(2) becomes:
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