Brodie's gourmet pretzel shop specializes in selling the very finest chocolate covered pretzels. banky bought 4 white chocolate pretzels and 6 dark chocolate pretzels for $10.50. holden bought 8 white chocolate pretzels for $9.75

Johnny rode his bike to a friends house 4 blocks down the street in his neighborhood. he immediately rode back home once he realized his friend was unable to play. what was his displacement for the total bike ride trip? what could you use as a reference point ? show the steps to solve this problem.