Round 10,400 to the nearest thousand

Two florida panthers were weighed. one weighs 6x+21 pounds and the two together weigh 14x+11 pounds how much does he other panther weigh alone

Which statements describe the solutions to the inequality x< -20 check all that apply. there are infinite solutions. each solution is negative. each solution is positive. the solutions are both positive and negative. the solutions contain only integer values. the solutions contain rational number values.

Julie begins counting backwards from 1000 by 2’s and at the same time tony begins counting forward from 100 by 3’s.   if they count at the same rate, what number will they say at the same time?