Question 1:Multiply both sides of the proportion by 35.
You get.
7(x-1) = 4x+2
7x-7 = 4x+2
Now, add both sides by 7 and subtract both sides by 4x
3x = 9
Divide both sides by 3
x=3
Question 2:Multiply both the numerator and the denominator of
by 3.
We want to multiply it by 3 so that the +1 and +3 become +3 and +9. +3 and +9 have a difference of 6, just like 15 and 21, which is what we want.
Set the numerator equal to the numerator and the denominator equal to the denominator.
3x+3 = 15
3x+9 = 21
If you solve both of these, you get x=4 for both.
That's your answer.
Hope this helps! :)