Question

Explain why you can’t solve this problem: (-2)^x=15

Answer 1

(-2)^x=15 is an equation that represents an exponential function, with base -2 and exponent x. However, this equation has no real solution, because the base of an exponent must be positive and -2 is not a positive number. Therefore, raising -2 to any power will always result in a negative number and can never be equal to 15 which is a positive number.

Answer 2

See below

Explanation:

Since the right side of equation (15) is positive, this means that x-value is even power since the only way for (-2)^x to be positive is when x = even number.

This also means that x can only be positive even integers (0, 2, 4, 6, 8, ...) since negative integer results in fraction.

However, there are no positive even numbers that make the equation true. Hence, why the equation results in null.