Andrei has a glass tank. first, he wants to put in some marbles, each of which has a volume of 0.4 liters. then, he wants to fill the tank with water until it's completely full. if he uses 50 marbles, he will have to add 33 liters of water. what is the volume of the tank? andrei has exactly 20 liters of water. how many marbles does he need so the tank is full?

1)

First, he wants to put in some marbles, each of which has a volume of 0.4 liters.

Then, he wants to fill the tank with water until it's completely full.

If he uses 50 marbles, he will have to add 33 liters of water.

This means the volume of water that can be filled using 50 marbles is:

50×0.4=20 liters.

Also, total volume of tank is:

volume filled by 50 marbles+33 liters of water.

=20+33=53 liters.

Hence, Volume of tank=53 liters.

2)

If Andrei has exactly 20 liters of water.

Let n marbles be used.

Hence,

53=20+n×0.4

33=0.4n

n=33/0.4

n=82.5

Hence, she needs to use 83 marbles.

step-by-step explanation:

let

we know that

the y-intercept is the y-coordinate of the point when the value of x is equal to zero

so

the y-coordinate of the point a is the y-intercept

the answer part a) is

the value of y-intercept is

part b) find the slope m

we know that

the value of the slope is equal to

substitute the values

therefore

the answer part b) is

the value of the slope is equal to

the general answer is

the slope is

the value of y-intercept is