`{:("Quantity A","Quantity B"),(x,12):}`

{:("Quantity A","Quantity B"),(x,y):}

{:("Quantity A","Quantity B"),(y,10):}

{:("Quantity A","Quantity B"),(x+y,2x):}

{:("Quantity A","Quantity B"),(x,3x-4):}

{:("Quantity A","Quantity B"),(y-x,50):}

x is a non - negative even integer. {:("Quantity A","Quantity B"),(x,1):}

x^(2)-2x-15=0 {:("Quantity A","Quantity B"),(x,1):}

x=4 {:("Quantity A","Quantity B"),(|2-x|,2):}

xy gt 0 {:("Quantity A","Quantity B"),(x+y,0):}

O is the center of the circle. The area of the circle is 16pi . The area of the shaded region lt 4pi . {:("Quantity A","Quantity B"),(x,90):}