Question

7. The product of two consecutive odd numbers is 399. Find the sum of the squares of the numbers.​

Answer 1

802

Explanation:

Let x stand for one of the numbers.

"consecutive" means in a row. So consecutive odd numbers are like 1, 3, 5, 7, 9, 11, 13... SO you could just guess and check. Like, 20×20 is 400 so 19×21 is a good guess and it works, so ??? you could just run with it from here. Buuuut,

the math is

x is a number (hopefully, ODD)

x + 2 would be the next odd number.

x(x+2) = 399

x^2 + 2x = 399

x^2 + 2x - 399 = 0

(x - 19)(x + 21) = 0

x-19=0 and x+21=0

x=19 and x= -21

We'll use the 19. So the next odd number is 21. But don't stop there. Re-read the question...they mysteriously want the sum (adding) of the squares (2nd power)

19^2 + 21^2

= 361 + 441

= 802

Answer 2

solution set

1:19 and 21

solution set

2:-21 and -19