Xmax -Xmin =?

Number Theory Level 3

If x is an integer and $9<{ x }^{ 2 }<99$ , then what is the difference between its MAX and MIN value of x?

3 solutions

Isaac Jiménez
Jun 13, 2014

Let observe that the MAX value of $x$ is $9$ , and the MIN possible value is $-9$ . So the difference is $18$

But -10 is the min possible integral value of the given inequality

Wrik Bhadra - 6 years, 5 months ago

How so?

$(-10)^2=100\not\lt 99$

Prasun Biswas - 6 years, 3 months ago

Very Brillian (^.~)

Earl Rich Diolan - 6 years, 1 month ago

Rama Devi
May 26, 2015

We observe that the maximum value is 9 and the minimum value is -9.Therefore their difference is 9-(-9) which is equal to 18.

Gacon Noname
Jun 6, 2014

|x| =< 9 so, 9 - (-9) = 18