What does decreasing the constant c by 5 units in an equation of the form y = x(to the second power) - 3x + c do to its graph?

The angles in a triangle are represented by 5x, 8x, and 2x+9. what is the value of ? a.10.8 b.11.4 c.9.7 d.7.2

Math i have no idea how to do a and b

If mary had 320 toy cars and she gave her friend 50 cars and then she gave her brother 72 more cars how much toy cars would mary have left ● explain with proper details