Question

Which statement is NOT true?

If x = 10, then x2 = 100.
x2 = 100 if and only if x = 10 or x = –10.
If x = –10, then x2 = 100.
If x2 = 100, then x = 10.

Answer 1

the last one is not true, because if \(x^2=100\) then it is possible that \(x=10\) but it is also possible that \(x=-10\)