What is the fraction and the percentage of 15

Complete the standard form of the equation that represents the quadratic relationship displayed above, where a, b, and c are rational numbers.

Long division setup showing an incomplete calculation. 12 is in the divisor, 6839 is in the dividend, and 5 hundreds and 6 tens is written in the quotient. 6000 is subtracted from 6839 to give 839. an unknown value represented by a box is being subtracted from 839. what number should be placed in the box to complete the division calculation?

597008.439431 to the nearest thousand