Question

Answer 1

a) \(\dfrac{x}{5}=\dfrac{y}{-7}=\dfrac{x+y}{5+\left(-7\right)}=\dfrac{-22}{-2}=11\\ x=55;y=-77\)

b) \(\dfrac{x}{y}=\dfrac{-3}{11}\\ \dfrac{x}{-3}=\dfrac{2y}{22}=\dfrac{x-2y}{-3-22}=\dfrac{50}{-25}=-2\\ x=6;y=-22\)

c) \(x:y:z=3:5:7\\ \dfrac{x}{3}=\dfrac{y}{5}=\dfrac{z}{7}=\dfrac{x-z}{3-7}=\dfrac{-24}{-4}=6\\ x=18;y=30;z=42\)

d) \(15x=5y=3z\\\dfrac{2x}{2}=\dfrac{y}{3}=\dfrac{z}{5}=\dfrac{2x-y-z}{2-3-5}=\dfrac{-18}{-6}=3\\ x=3;y=9;z=15\)