How do you write 1 is to 2 as 5 is to x

as a proportion in fractional notation?(1 point)
Responses

21=5x

Start Fraction 2 over 1 End Fraction equals Start Fraction 5 over x End Fraction
12=5x
Start Fraction 1 over 2 End Fraction equals Start Fraction 5 over x End Fraction
1:3::5:x
ratio of 1 to 3 colon colon ratio of 5 to x
1:2=5:x

Start Fraction 1 over 2 End Fraction equals Start Fraction 5 over x End Fraction