How do you solve x=25x?

1 Answer
Aug 5, 2015

x=0 and x=1625

Explanation:

First, rewrite your equation by cancelling the minus sign

x=25x

Right from the start, it's obvious that any solution you find must be positive, x0, since the square root of a negative number does not have a real number as a solution.

So, square both sides of the equation to get

(x)2=(25x)2

x=625x2

Move everything to one side of the equation and factor the resulting expression

625x2x=0

x(625x1)=0

This equation is equal to zero when wither x=0 or when (625x1)=0, which is equivalent to having

625x1=0x=1625

Both solutions are valid because they satisfy the condition x0.