SOLUTION: what rational numbers are roots of the equation (X2-7)(X2-9)=0

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Question 84550: what rational numbers are roots of the equation (X2-7)(X2-9)=0
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
what rational numbers are roots of the equation (X2-7)(X2-9)=0
%28x%5E2-7%29%28x%5E2-9%29=0
x%5E2-7=0 or x%5E2-9=0
x%5E2-7%2B7=0%2B7 or x%5E2-9%2B9=0%2B9
x%5E2=7 or x%5E2=9
sqrt%28x%5E2%29=%2B-sqrt%287%29 or sqrt%28x%5E2%29=%2B-sqrt%289%29
x=%2B-sqrt%287%29 or x=+/-3
%2B-sqrt%287%29 are irrational, but +/- 3 are rational, so your answers are:
highlight%28x=-3%29 or highlight%28x=3%29
Happy Calculating!!!