McGraw Hill Integrated II, 2012
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McGraw Hill Integrated II, 2012 View details
Study Guide and Review
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Exercise 9 Page 217

Use the given roots to write the equation in factored form. Then multiply and simplify to obtain the standard form.

Example Solution: 6x^2-31x+5=0

Practice makes perfect
We can write a quadratic equation in factored form using the given roots. Then we will change it to standard form by multiplying the factors. Factored Form:& a(x-p)(x-q)=0 Standard Form:& ax^2+bx+c=0 In the factored form, p and q are the roots of the equation. Since we are told the roots are 16 and 5, we can partially write the factored form of our equation. a( x-1/6 ) ( x-5 )=0 Since a does not have any effect on the roots, we can choose any value. For simplicity and in order to have integer coefficients, we will let a=6. This is a common multiple of both denominators of the given roots and will allow us to eliminate the fractions when we distribute. 6( x-1/6 ) ( x-5 )=0 Finally, let's use the Distributive Property to obtain the standard form.
6( x-1/6 ) ( x-5 )=0
( 6x-1) ( x-5 )=0
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Multiply parentheses
6x(x-5)-1(x-5)=0
6x^2-30x-1(x-5)=0
6x^2-30x-x+5=0
6x^2-31x+5=0
Please note that this is just one example of a quadratic function that satisfies the given requirements.