Which of the relations below is a function? {(blue, bird) (red, car) (yellow, bus) (yellow, taxi)}

{ (red, sign) (yellow, sign) (red, light) (green, light)}

{(red, apple) (purple, grape) (yellow, banana) (green, pear)}

Ifound this on google “that means that the graph of a function with direct variation has these features: it is a straight line: because the slope is the ratio y/x = k. it passes through the origin (0,0): because y = kx = k (0) = 0.” i hope this you for what your looking for