\(\dfrac{x}{12}=\dfrac{y}{13}\) và \(3x+2y=124\)

\(\dfrac{x}{2}\)=\(\dfrac{y}{3}\)=\(\dfrac{z}{6}\) và 3x-2y+2z=24

a) \(\dfrac{5}{7}\)+\(\dfrac{3}{4}\).\(\dfrac{-11}{2}\)

b) (\(\dfrac{12}{17}\)+\(\dfrac{19}{7}\)) - (\(\dfrac{-5}{17}\)-\(\dfrac{3}{7}\))

c) (0,125)\(^{12}\).(-8)\(^{12}\)-\(\dfrac{45^3}{15^3}\)

d) \(5\dfrac{2}{7}\).(\(-\dfrac{1}{3}\))-\(2\dfrac{2}{7}\).(\(-\dfrac{1}{3}\))

e) \(\dfrac{9^2.9^3}{3^9}\)

(4x - 7)\(^2\) - 5 . |7 - 4x| = 0