Question

Seven years ago,Rishik was seven times as old as his son Vihaan . After three years, Rishik will be three times as old as Vihaan.Represent this situation algebraically and graphically.

Answer 1

let age of vihaan , 7 years ago was x years

so age of rishik , 7 years ago was 7x


today's their ages,

vihaan -- x + 7

rishik -- 7x+7


after three years

age of vihaan -- x + 7 + 3 = x + 10

age of rishik -- 7x+7 + 3 = 7x+ 10


now 7x+ 10 = 3 ( x + 10 )

7x + 10 = 3x + 30

7x - 3x = 30 - 10

4x = 20

x = 5

so vihan s today's age is

x+7 = 5+7 = 12

and

rishiks today's age is
7x+ 7 = 7 ×5 + 7 = 35 +7 = 42