Line x line y find the measures of angle 4

The parabola y = x² - 4 opens: a.) up b.) down c.) right d.) left

Li buys supplies so he can make and sell key chains. he begins to make a profit only after he sells 4 key chains. what point on the graph makes the most sense in this situation?

What can each term of the equation be multiplied by to eliminate the fractions before solving? x – + 2x = + x 2 6 10 12