7 = r^1/2 is the same as saying 7 = square root of r. So, to get rid of the square root sign on the r, you need to square it, and when you do something to one side of the equation, you have to do the same to the other side. So after squaring both sides, you get 49 = r.
I think the answer is ;B.316 and 38
The difference in salary is 36000-28000=8000
The difference in annual increase is 3000-2000=1000
Therefore it takes 8000/1000= 8 years to catch up.
At the end of eight years,
Salary with the first company = 28000+8*3000=52000
Salary with the second company = 36000+8*2000=52000
Let the triplets' age be x, the sister's age is then x-5.
product of their age as given
xÂł.(x-5)=75749+x+x+x+x-5
x^4 - 5xÂł= 4x +75744
x^4 - 5xÂł -4x -75744=0
resolving the equation,
we get
x = 18
therefore, Age of ben,bob and bill is 18
so , age of stephanie is x-5 = 18-5 = 13
stephanie is 13 years old.
