Question 619162
You must rearrange.

6f + 1 = 10

You want to solve for f so you need to have the f on one side and the regular numbers on the other.
This means that you would need to move the 1 over to the right side of the equal sign as so:

6f = 10 - 1

note when I moved the 1 to the other side I changed the sign before it to -

((Some teachers may want you to write an intermediate step:

6f + 1 - 1 = 10 - 1 i.e. taking away the 1 from each side in order to move it
which leads to the +1 and -1 on the left cancelling each other out, but I was never shown to do it that way.))

So you have 6f = 10 - 1
so 6f = 9

now you want to find f, so you have to change 6f to f and you do this by dividing 6f by 6, but to do this you want to keep each side of the equation equal so if you divide the 6f by 6 you also need to divide everything else by 6, in this case 9 so:

{{{6f/6 = 9/6}}}

f = 1 1/2

( I assume you know how to simplify a fraction, in this case 9/6 became 1 1/2 or if you need the answer in decimals: 1.5

so f= 1.5 or 1 1/2 if in fractions.