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Write numerical coefficient of y² in the expression 2x² - 15xy – 7y²

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.

Multiply and simplify. 2x^2 y^3 z^2 · 4xy^4 x^2 i will mark you brainliest if right. show how you got the answer, !