So 1/9-16z^2 this is a diffirence of two perfect squares thing
so (1/3)^2-(4z)^2
so ((1/3)-4z)((1/3)+4z)
7 lb will cover an area of 1 square foot, while 315 lb will cover an area of 45 square feet.
From given question,
252 lb = 36 ft² ..........(1)
The number of pound for an area of 1 square foot is calculated as follows:
x = 1 ft² .......(2)
The area and the amount of gravel are illustrations of proportions.
From (1) and (2) we get an equation,
⇒ x × 36 = 252 × 1
⇒ x = 252/36
⇒ x = 7 lb
We need to find the area that could be covered with 315 lb of gravel
The area to be covered with 315 lb gravel is calculated as follows:
315 lb = y ............(3)
From (1) and (3) we get an equation,
⇒ y × 252 = 36 × 315
⇒ y = 45 ft²
Therefore, 7 lb will cover an area of 1 square foot, while 315 lb will cover an area of 45 square feet.
Learn more about the proportions here:
brainly.com/question/13114933
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Answer:

Step-by-step explanation:
1. Swap sides

Swap sides:

2. Isolate the y

Multiply to both sides by 18:

Group like terms:

Simplify the fraction:

Multiply the fractions:

Simplify the arithmetic:

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Why learn this:
- Linear equations cannot tell you the future, but they can give you a good idea of what to expect so you can plan ahead. How long will it take you to fill your swimming pool? How much money will you earn during summer break? What are the quantities you need for your favorite recipe to make enough for all your friends?
- Linear equations explain some of the relationships between what we know and what we want to know and can help us solve a wide range of problems we might encounter in our everyday lives.
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Terms and topics
- Linear equations with one unknown
The main application of linear equations is solving problems in which an unknown variable, usually (but not always) x, is dependent on a known constant.
We solve linear equations by isolating the unknown variable on one side of the equation and simplifying the rest of the equation. When simplifying, anything that is done to one side of the equation must also be done to the other.
An equation of:

in which
and
are the constants and
is the unknown variable, is a typical linear equation with one unknown. To solve for
in this example, we would first isolate it by subtracting
from both sides of the equation. We would then divide both sides of the equation by
resulting in an answer of:
