Scientific notation must have how many non zero digits to the left of the decimal point

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.

Kayaks rent for $35 per day. which expression can you use to find the cost in dollars of renting 3 kayaks for a day?

Rewrite the following quadratic functions in intercept or factored form. show your work. f(x) = 3x^2 - 12