May you please Simplify this for me

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There are 20 children in the cast of a class play and 8 of the children are boys of the boys 4 have a speaking part in the play and of the girls 8 do not have a speaking part in the play if a child from the cast of the place chosen at random what is the probability that the child has a speaking part

Thelime contains the point(-3,0) and parallel x-3y=3( show all work)

If 1/√5+1/√5+1=p+q√r , find the values of p, q and r