# Find the Unknown Variable

• October 21st 2012, 04:16 PM
KayPee
Find the Unknown Variable
Two numbers are each multiplied by themselves to give two new numbers. The difference between these two new numbers is less than ten; the difference between the two original numbers was one.
The two original numbers added together was more than 7. What is one of the original numbers?

Let the original numbers be a and b

And so new numbers are a^2 and b^2-Two numbers are each multiplied by themselves to give two new numbers.

a^2 - b^2 < 10- The difference between these two new numbers is less than ten.

a-b = 1 -The difference between the two original numbers was one.

a + b > 7 -The two original numbers added together was more than 7.

What do I need to do further to unravel this?
• October 21st 2012, 04:40 PM
skeeter
Re: Find the Unknown Variable
note ...

$a^2 - b^2 = (a-b)(a+b)$
• October 31st 2012, 02:58 AM
KayPee
Re: Find the Unknown Variable
Thnx But am still confused as to how I can go any further to unravel this question to find the answer to the question:

What is one of the original numbers?
• October 31st 2012, 03:41 AM
$(a-b)(a+b)<10$
$(a+b)>7$
$(a-b)=1$
so: $7