Answer:
x = 5
Step-by-step explanation:
Given that,
[tex]63:(5x-3x-1)=21:3\\\\or\\\\\dfrac{63}{(5x-3x-1)}=\dfrac{21}{3}\\\\\dfrac{63}{(2x-1)}=7[/tex]
Cross multiplying both sides,
[tex]63=7(2x-1)\\\\9=2x-1[/tex]
Taking like terms together,
[tex]10=2x\\\\x=5[/tex]
So, the value of x is equal to 5.