Find the least common denominator for these two rational expressions negative 4/x^2 6/9x

Factor -8x3-2x2-12x-3 by grouping what is the resulting expression?

Identify the initial amount a and the growth factor b in the exponential function. a(x)=680*4.3^x

The mean of 10 values is 19. if further 5 values areincluded the mean becomes 20. what is the meanthese five additional values? a) 10b) 15c) 11d) 22