You asked a friend to think of a nonnegative number, add two to
the number, square the number, multiply the result by 3 and
divide the result by 2. If the result is 54, what is the original
number?
Answers
Answered by
0
(3x^2+12+12x)/2=54
Cross multiplication
3x^2+12+12x=108
3x^2+12x-96=0
Splitting middle term
3x^2-12x+24x-96=0
Taking common
3x(x-4)+24(x-4)=0
(x-4) (3x+24)=0
x=4;x=-8
So x=4
Cross multiplication
3x^2+12+12x=108
3x^2+12x-96=0
Splitting middle term
3x^2-12x+24x-96=0
Taking common
3x(x-4)+24(x-4)=0
(x-4) (3x+24)=0
x=4;x=-8
So x=4
Similar questions