Find all the numbers with the property that when the number is added to itself the sum is the same as when...?

Question

Find all the numbers with the property that when the number is added to itself the sum is the same as when the number is multiplied by itself.

What's the best way to go about solving this question?

Answer 1

If the number is x, then by adding it to itself you get x+x = 2x, and by multiplying it by itself you get x*x = x^2. So we want
x^2 = 2x
<=> x^2 - 2x = 0
<=> x(x-2) = 0
<=> x = 0 or x-2 = 0
<=> x = 0 or x = 2.

Answer 2

0 and 2

Answer 3

what u have stated is that x^2=2x

so x must be 2 or 0