Answer:
X ≥9 years after 2009.
Step-by-step explanation:
Y=4x+4
Y-4=4x
X=(Y-4)/4
Y=number of U.S. households, in millions.
Y≥40
Y-4≥36
(Y-4)/4≥9
So, X≥9.
Answer:
528 cm²
Step-by-step explanation:
First I would calculate the area of the side rectangles:
20 x 9 = 180 cm²
There are two identical rectangles on both sides so i would x2
180 x 2 = 360 cm²
The area of the middle rectangle:
6 x 20 = 120 cm²
The area of the triangles:
Area of a triangle = (Base x Height)/2
8 x 6 = 48
48 ÷ 2 = 24
There are two identical triangles on the bottom and the top so x2
24 x 2 = 48
Now add all the values up:
360 + 120 + 48 = 528 cm²
I hope this helps!
Answer:
450 minutes
Step-by-step explanation:
Given
w = 45000 - 100t
Required
Determine how long it'll take to empty the pool
Being empty means there's no water in the pool.
So, we have to set w to 0 to get the value of t
i.e w = 0
Substitute 0 for w in w = 45000 - 100t
0 = 45000 - 100t
Collect Like Terms
100t = 45000
Divide through by 100.
t = 450
Hence, it'll take 450 minutes to empty the pool