Abathtub is draining at a constant rate. after 2 minutes, it holds 35 gallons of water. four minutes later, it holds 15 gallons of water. write an equation that represents the number y of gallons of water in the tub after x minutes

First find the rate or slope...

(y2-y1)/(x2-x1)=(15-35)/(4-2)=-20/2=-10

so far we have:

y=-10x+b, now we can use either point to solve for b, the y-intecept (initial amount)  I'll use (4,15)

15=-10(4)+b

15=-40+b

b=55

so the equation for the bathtub is:

y=-10x+55

the law of definite proportions states samples of a compound will always contain the same proportion of elements by mass. in other words, a given compound will always contain the same elements in the same proportions by mass.the law of multiple proportions states when two elements combine with each other to form more than one compound, then the weights of one element that combine with a fixed weight of the other are in a ratio of small whole numbers.