Question

3/x = x/12 what is x? Plz help

Answer 1

x = ± 6

Explanation:

Given

`(3)/(x)` =
`(x)/(12)` ( cross- multiply )

x² = 36 ( take the square root of both sides )

`√(x^2)` = ±
`√(36)`, that is

x = ± 6

Answer 2

`\text{Solve for x:}\\\\(3)/(x)=(x)/(12)\\\\\text{Multiply both sides by x}\\\\3=(x)/(12)x\\\\\text{Multiply both sides by 12}\\\\36=x\cdot x\\\\36=x^2\\\\\text{To format it, subtract 36 and}\,\,x^2\text{ on both sides}\\\\-x^2=-36\\\\\text{Divide both sides by -1}\\\\x^2=36\\\\\text{Square root:}\\\\\sqrt x^2=\pm\sqrt36\\\\\boxed{x=6\,\,or\,\,x=-6}`