Pls pls help I'm almost done

How can you find the conditional probability of a given b as the fraction of b’s outcomes that also belong to a, and interpret the answer in terms of the model? i just need a good explanation

Solve each quadratic equation by factoring and using the zero product property. x^2 - 8x + 30 = 3x

Solve the following: 12(x^2–x–1)+13(x^2–x–1)=25(x^2–x–1) 364x–64x=300x