Math / Linear Equations
posted by Ashley on .
I was looking on a website that teaches linear algebra and it had this problem:
3x  15
_______ =0
2x + 1
And it says the answer is: x = 5
But I don't understand how to get that answer so I hope someone can give me step by step directions for it.

As long as x≠1/2, the denominator is not zero. In that case, the only way for the expression to be zero is when the numerator becomes zero, or
3x15=0, which gives x=5 as the root.
In the case when x=1/2, the expression becomes undefined, and no solution is possible.