The product of two numbers is 21 and their sum is 10, what are the numbers

Answer 1

If you are looking for whole numbers, I can think of only two numbers so that
3 x 7 = 21, and it so happens that 3+7 = 10
How easy was that?

Answer 2

Eq1: x * y = 21.In Eq1, replace X with
y = 21/x.

Eq2: x + y = 10.

In Eq2, replace Y with 21/x and solve for X:
x + 21/x = 10.
Multiply both sides by X:
x^2 + 21 = 10x,
x^2 - 10x + 21 = 0,
(x-3)(x- 7) = 0,
X = 3, or X = 7.

In Eq1, replace X with 3 and solve for Y:
3 + Y = 10,
Y = 7.

y
= 7.

Answer 3

Note: The first line of my response should be Eq1: x * y = 21.