Consider expression 
First, you can factor it:
Since x is integer number, then you can see that x-1 is previous integer number (x-1 is 1 unit smaller than x).
Therefore, x-1 and x are two consecutive integers. When you have two consecutive integers, one of them is always even and one is always odd. Multiplying even integer number by odd integer number you always get even integer number.
Thus, 
is always even.
Answer:
a) 1.8 × 10^-12 cm³ or 1.8 × 10^-12 cubic meters
b) 7.1 × 10^-6 mm² or 7.1 × 10^-6 square millimeters
Step-by-step explanation:
a) We are assuming that the shape of the bacteria is a sphere.
Hence, Volume of the Sphere(Bacteria) = 4/3 × π × r³
Diameter = 1.5 μm
Radius = Diameter/2 = 1.5μm/2
= 0.75μm
We are told that the volume should be in cubic centimeters
Converting 0.75μm to centimeters
1 μm = 1 × 10^-4 cm
0.75 μm =
Cross Multiply
= 0.75 μm × 1 × 10^-4 cm/ 1 μm
= 0.000075cm
Volume of the Sphere(Bacteria) = 4/3 × π × r³
= 4/3 × π × (0.000075)³
= 1.767145867 × 10^-12 cm³
Approximately as 2 significant figures = 1.8 × 10^-12 cm³
b) The formula for the Surface area of a Sphere = 4πr²
Diameter = 1.5 μm
Radius = Diameter/2 = 1.5μm/2
= 0.75μm
We are told that the surface area should be in square millimeters
Converting 0.75μm to millimeters
1 μm = 0.001 mm
0.75 μm =
Cross Multiply
= 0.75 μm ×0.001mm/ 1 μm
= 0.00075mm
Surface Area of a Sphere
= 4 × π × r²
= 4 × π × 0.00075²
= 7.06858 ×10^-6 mm²
Approximately to 2 significant figures
= 7.1 × 10^-6 mm²
Answer :y=4 x=2
Step-by-step explanation:
The house with 30000 cubic foot costs less to cool per cubic foot than the house with 25000 cubic foot.
Step-by-step explanation:
The cost of cooling 30000 cubic foot house = $7
Cost per cubic foot = 7/30000
=$0.00023
The cost of cooling 25000 cubic foot house= $6.50
Cost per cubic foot=6.50/25000
= $0.00026
The house with 30000 cubic foot costs less to cool per cubic foot than the house with 25000 cubic foot.
Answer:
Step-by-step explanation:
The result is given by means of some algebraic handling:
- Multiplication of rationals.
- Dividing each term by 2.
- Dividing each term by 2.
- Dividing each term by 3.
