She should distribute the 3( it becomes y-6=3x-9) and then isolate the y by subtracting 6 on both sides( it becomes y=3x-9-6). That is not the final answer since she can still simplify it. To simplify she would add like terms, in this case it is -9 and -6. The final equation would be: y=3x-15. The slope is 3x and the y intercept is -15