Question

Find 2 numbers who product is 15 and sum is 16.​

Answer 1

15 and 1

Explanation:

x and y are two numbers.

Two equations:

x · y = 15

x + y = 16

Rearrange one of the equations (I'll rearrange the sum equation):

x + y = 16

x = 16 - y

Substitute that to the other equation and solve for y:

x · y = 15

(16 - y) · y = 15

16 - y · y = 15

16 - y² = 15

-y² = 15 - 16

-y² = -1

y² = 1

y = √1

y = 1

Now substitute that to any of the equation and solve for x (in here, I'll choose the multiplication one):

x · y = 15

x · 1 = 15

x = 15

Now verify:

15 · 1 = 15

15 + 1 = 16

This is correct