How do you solve $x^2=7$ ?

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Answer 1 · 2017-01-17T00:08:28

$x = sqrt(7)" "$ or $" "x=-sqrt(7)$

By definition, a square root of $7$ is a number which when squared gives $7$ .

So one solution is $x=sqrt(7)$ (the positive square root of $7$ ) since $(sqrt(7))^2 = 7$

The other solution is $-sqrt(7)$ since $(-sqrt(7))^2 = (-1)^2*7 = 7$

Any non-zero number has exactly $2$ square roots. If the original number is negative then those square roots are so called imaginary numbers.

[[ The term imaginary is rather unfortunate as such numbers are just as 'real' as Real numbers ]]

How do you solve x^2=7x^2=7?