1/x+4=8

In the first one, IF u solve for x the answer comes to 0.625 or 5/8. So substitute the value of x into the second equation the answer comes to 9.6 or 48/5.

But IF my guess is right so in the first one the equation is $\frac{1}{x} + 4=8$ and u see that in the 2^nd equation its $\frac{1}{x} +8$ then the answer should be 16 cuz since +8 is 2 times +4 so then the answer will also be *2.

Hope u got my point.

1/x+4=8,  then 1/x+8 equals

1/x + 4 = 8    subtract 4 from both sides

1/x =4            cross multiply

4x = 1             divide both sides by 4

x = 1/4

1/x+8 =       sub 1/4 for x

1/(1/4) + 8 =

1 x 4 + 8 =12

1/x + 4  =  8       Subtract  4  from both sides of the equation.

1/x  =  8 - 4

1/x  =  4

So.......

1/x + 8               Since  1/x = 4 , we can substitute  4  in for 1/x .

=  4 + 8

=  12

Here's probably the easist method of all!