SOLUTION: Find the quadratic equation with integral coefficient whose roots are 9 +- (plus or minus) i

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Question 876013: Find the quadratic equation with integral coefficient whose roots are 9 +- (plus or minus) i
Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website!
the roots are 9 +/- i

start with x = 9 + i and x = 9 - i

to get the factors, set these equations equal to 0.

you do that as follows:

x = 9 + i
subtract 9 and subtract i from both sides of the equation to get:
x - 9 - i = 0

x = 9 - i
subtract 9 and subtract i from both sides of the equation to get:
x - 9 + i = 0

your factors are:

(x - 9 - i) and (x - 9 + i)

now you have to multiply these factors together:

use your distributive law to do this.

look at the picture to see the calculations.

the next picture shows the factoring of the quadratic equation to confirm the solution is good.

any questions, send me an email.