i have answers but im not sure if there correct but ill write them down anyway a.6 b.2,3,6,9 c.first of all its spelled dice not die and yes because it all equals 100:)

Micah did not explain the last step correctly. You cannot cross out a term from the numerator and denominator unless it is a factor. In other words, x² needed to be multiplied and not added in order to cross it out.
4x^2+25=4x^2=-25=x^2=-25/4 has no solution. because, negative number do not live under radical except complex number
18% I believe. Because you do the math then you rounded out and then I get 18%