Question

Is 1/2x=21 42 i need to be sure

Answer 1

well if you equation is 1/2x=21 then you answer would be x=21

because if you make 1/2 a decimal it is 0.5 and you want to have x alone so you would divide 1/2 by 0.5 and then you would have 1x=21 which is x=21

Answer 2

1/2x=21
That means if you take half of the x value, it would be 21. All you have to do in this situation is to double 21. So yes, it is 42.