Question

the sum of two numbers is 15 and thu sun of their square is 113. find the number​

Answer 1

Let the numbers be x and (15 - x).

Then,x²+(15−x)²=113?  

=> x²+225+x²−30x=113  

=> 2x2−30x+112=0  

=> x²−15x+56=0

=> (x - 7) (x - 8) = 0  

=> x = 7 or x = 8.

So, the numbers are 7 and 8.