# Finding the sum of the digits of the number

• Jan 5th 2012, 01:56 PM
stevecowall
Finding the sum of the digits of the number
Compute the sum of the digits of the number given by

Attachment 23189
If a<b, ab = 6 and a + b = 5.

I was putting a = 5-b and substitute in but unable to solve it. Appreciate if you show me how to solve it.
• Jan 5th 2012, 02:07 PM
pickslides
Re: Finding the sum of the digits of the number
Quote:

Originally Posted by stevecowall
If a<b, ab = 6 and a + b = 5.

you have $a=5-b$ so $(5-b)b=6 \implies b^2-5b+6=0$

Can you solve this quadratic?
• Jan 5th 2012, 02:08 PM
ILikeSerena
Re: Finding the sum of the digits of the number
Welcome to MHF, stevecowall! :)

How many ways do you know to factorize ab=6?
• Jan 5th 2012, 04:48 PM
stevecowall
Re: Finding the sum of the digits of the number
Thank you I have figure it out already thanks so much