Help guys, I need to finish this, please.

For what interval of x is f(x)<0

What is the missing reason in the proof? segment addition congruent segments theorem transitive property of equality subtraction property of equality?

Luke started a weight-loss program. the first week, he lost x pounds. the second week, he lost pounds less than times the pounds he lost the first week. the third week, he lost 1 pound more than of the pounds he lost the first week. liam started a weight-loss program when luke did. the first week, he lost 1 pound less than times the pounds luke lost the first week. the second week, he lost 4 pounds less than times the pounds luke lost the first week. the third week, he lost pound more than times the pounds luke lost the first week.

If f(x)=-3x+2 and g(x)=-7x-2, which point represents f(x)=g(x)?