
solve for "r", to see what the radius is
keep in mind that, the diameter is just "2r"
Answer:
Area of triangle = 15 square units
Step-by-step explanation:
We need to find area of the triangle, given the vertices:
A=(4,0)
B=(1,5)
C=(7,5)
The formula used is: 
We have: 
Putting values and finding area

We will be ignoring negative sign, because area of triangle is positive.
So, Area of triangle = 15
No, permutation is for finding out orders like how many ways can you arange the letters x,y,z the answer is 6, because xyz, xzy, yxz, yzx, zyx, zxy
permutations are a branch of probability
probability is (desired outcomes)/(total possible outcomes) or
10/total people registered