You're in luck because two of them disappear when you see that 4.6 goes exactly 8 times into 36.8. If you multiply the original equation by 10 on each side you get: 46(x+5.1)=368. Divide each side by 2: 23(x+5.1)=184 and then divide each side by 23: x+5.1=8. All we have to do now is subtract 5.1 from each side: x=8.0-5.1=2.9. Treat this subtraction by ignoring the decimal point: 80-51=29 and putting it back afterwards: 2.9.