Hey can you help me fast!!!

How do you find the area of a triangle

If the tip varies directly with the number of guest which equation represents between the tip,t, and the number of guest,g?

Astudent draws two parabolas both parabolas cross the x axis at (-4,0) and (6,0) the y intercept of the first parabolas is (0,-12). the y intercept of the second parabola is (0,-24) what is the positive difference between the a values for the two functions that describe the parabolas