A parabola can be represented by the equation x2 = - 20y.
What are the coordinates of the focus of the parabola?
O(-5,0)
O (5,0)
0 (0,5)
0 (0,-5)

If square root x = -7, then x= -49 true or false

Thales was an ancient philosopher familiar with similar triangles. one story about him says that he found the height of a pyramid by measuring its shadow and his own shadow at the same time. if the person is 5-ft tall, what is the height of the pyramid in the drawing?

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?