Simplify $\frac{3x}{10}+\frac{5x+4}{10}$3x10+5x+410.
Simplify $\frac{7x}{11}+\frac{3x-2}{44}$7x11+3x−244.
Simplify $\frac{4x}{7}-\frac{2x-3}{21}$4x7−2x−321.
Simplify $\frac{8x^2}{11}+\frac{5x^2-2x}{55}$8x211+5x2−2x55.