Question

Factor 9b^2 - 4.

Answer 1

First thing to do is to set it equal to 0 so you have something to solve for. After that, you can add 4 to both sides to get \[9b ^{2}=4\]Divide both sides by 9 to isolate the b^2. Now, how do you "undo" a squared number? [take the square root of it, right?]. So take the square root of 4/9, and you get \[b=\pm \frac{ 2 }{ 3 }\] See that?