8. You find the probability P(A or B) by using the equation PA or B) = P(A) + P(B) - P(A and B).
Describe why it is necessary to subtract PA and B) when the events A and B are overlapping.
Then describe why it is not necessary to subtract P(A and B) when the events A and B are disjoint.

Step-by-step explanation:

When you add P(A) and P(B), the overlap P(A and B) is counted twice.  So you must subtract it to get the probability P(A or B).

If A and B are disjoint, then P(A and B) = 0, so it isn't necessary to subtract.

80 the answer is 80

step-by-step explanation:

the formula for the equation of a circle is (x – h)2+ (y – k)2 = r2, where (h, k) represents the coordinates of the center of the circle, and r represents the radius of the circle. if a circle is tangent to the x-axis at (3,0), this means it touches the x-axis at that point.