Answer:
1: 7x+19=40
2: 19+7x=40
Step-by-step explanation:
Answer:
A boat would need 21 liters to cover the distance of 84 km.
Step-by-step explanation:
Given
A boat can travel 496 km on 124 liters of fuel.
To determine
How much fuel will it need to go 84 km?
It is stated that:
Distance covered in 124 liters of fuel = 496 km
Thus,
Unit rate = 496 km / 124 liters
= 4 km per liter
Thus,
The distance covered in 1 liter = 4km
In order to determine the distance covered in 84 km, all we need is to divide 84 km by 4.
i.e.
The fuel needed to go 84 km = 84 / 4 = 21 liters
Therefore, a boat would need 21 liters to cover the distance of 84 km.
Answer:
To completely fill the sandbox will cost $56
Step-by-step explanation:
First, we calculate volume of the rectangular-shaped sandbox:

We know that density of sand is 100 pounds per cubic foot. Then, to fill the sand box that has a volume of 8 cubic foot, we calculate by rule 3:
1cubic foot..............100 pounds
8 cubic foot.............x pounds


We will need 800 pounds of sand to fill the sandbox, then we can calculate by rule 3 the number of bags needed and next the total cost of them:
50 pounds.......1bag
800 pounds.....x bags

To calculate the cost:
1 bag ..................$3.50
16 bags.................$x

To completely fill the sandbox will cost $56
X-doubling periods
Y-height of bamboo
Y=ab^x
1) make a table of values
X Y
1 5
2 10
3 20
2) write equations and substitute
5=ab^1 —> a=5/b^1 —> a=5/b
10=ab^2
Substitute into second equation
10=(5/b)*b^2
10=5b^2/b
10=5b
b=2
Substitute back in
b=2
10=a*2^2
10=4a
a=5/2
End equation:
Y=5/2*2^x