If 5/x = 15/x+20, what is the value of x/5?

Answer:
c) 2
Step-by-step explanation:
here you can use cross multiplication. that's where you turn the fraction into an equation. ( there's videos about it, I'm not very good at explaining )
so you can turn
[tex]\frac{5}{x} = \frac{15}{x + 20}[/tex]
into
5(x + 20) = 15x
5x + 100 = 15x
subtract 5x from both sides
100 = 10x
x = 10.
the value of x/5 would be 2, since 10/5 is 2.
Since x/5 is the reciprocal of 5/x, we know that we can flip the fraction on the right hand side will be flipped.
Thus, x/5 = (x + 20)/15
Now we cross multiply, 15x = 5(x + 20)
Simplify: 15x = 5x + 100
Subtract 5x from each side: 10x = 100
Divide 10: x = 10
Now plug 10 back into the right hand side: (10 + 20)/15
So, the answer is 2.