A number is such that square of its successor is successor of its 7 multiple. The number is?

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24 May 2010 Find the number

A number is such that square of its successor is successor of its 7 multiple. The number is?

OPtion

1) 8
2) 6
3) 7
4) 5
5) 9
6) 1
7) 2
8) 3
9) 4
10) 10

Solution

According to given condition (x+1)2 = 7x +1

On solving this equation, we get x = 5

Correct Option: 4 Best Solution (10)

Saswata Chakraborty   14 years AGO

(x+1)^2=7x+1
=>x^2-5x=0
=>x=0 or 5
so correct ans. is 5

Like? Yes (1) | No   

Dr.Dipin Singh   14 years AGO

A number is such that square of its successor is successor of its 7 multiple.

If x is the desired number, then

(x+1)^2= 7*x + 1

as x+1 is successive number and 7x+1 is successive number of its 7 multiple.

solving this we get x=5.

To check
6^2= 7*5+1 or 36 =35+1

Like? Yes (1) | No   

sivakumar   14 years AGO

(x+1)^2 = 7x+1; Solve it ; x=5

Like? Yes (1) | No   

SUDESHNA SEN   14 years AGO

As per the given condition,
(x+1)^2= 7x+1,
or, x^2+2x+1= 7x+1,
or, x^2-5x=0,
or, x(x-5)= 0,
or, x=0,5.
But x can't be 0, so x= 5..... Option 4)

Like? Yes (1) | No   

Mamon Sengupta   14 years AGO

As per the given condition,
(x+1)^2= 7x+1,
or, x^2+2x+1= 7x+1,
or, x^2-5x=0,
or, x(x-5)= 0,
or, x=0,5.
But x can't be 0, so x= 5..... Option 4)

Like? Yes (1) | No   

Trishita Dasgupta   14 years AGO

As per the given condition,
(x+1)^2= 7x+1,
or, x^2+2x+1= 7x+1,
or, x^2-5x=0,
or, x(x-5)= 0,
or, x=0,5.
But x can\'t be 0, so x= 5..... Option 4)

Like? Yes (1) | No   

~Sandeep~   14 years AGO

Assume no. to be x
(x+1)^2 = x*7+1 => x(x-5)=0 => x=5

Like? Yes (1) | No   

ASHOK ROY   14 years AGO

As per the given condition,
(x+1)^2= 7x+1,
or, x^2+2x+1= 7x+1,
or, x^2-5x=0,
or, x(x-5)= 0,
or, x=0,5.
But x can\'t be 0, so x= 5..... Option 4)

Like? Yes (1) | No   

sanjib biswas   14 years AGO

5 s successor 6^2=36=5*7 successor

Like? Yes (1) | No   

susmit   14 years AGO

(x + 1)^2= 7x + 1

Like? Yes (1) | No