Alexi divided 256 by 16. Which could he have been converting?

Elena and her husband marc both drive to work. elena's car has a current mileage (total distance driven) of 15,000 and she drives 23,000 miles more each year. marc's car has a current mileage of 46,000 and he drives 9,000 miles more each year. will the mileages for the two cars ever be equal? explain.

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Common binomial factor of 6x(3x+7)+5(3x+7)