Question

Kelly tells you that when variables are in the denominator, the equation one over two plus three over x equals three over four becomes unsolvable. Kelly explains, "There is a value for x that makes the denominator zero, and you can't divide by zero." Demonstrate to Kelly how the equation is still solvable and explain your reasoning.

Answer 1

1/2 + 3/x = 3/4
multiply everything by x
1/2x + 3 = 3/4x...subtract 1/2x from both sides
3 = 3/4x - 1/2x
3 = 3/4x - 2/4x
3 = 1/4x...multiply both sides by 4
4 * 3 = x
12 = x