Answer:
6,226 tiles of 9 in are needed to cover an area of 400 square feet
Step-by-step explanation:
Let
A -----> an area in square feet
t(A) ---> the total number of 9 in. tiles needed
we have

For A=400 ft^2
substitute in the equation and solve for t


That means -----> 6,226 tiles of 9 in are needed to cover an area of 400 square feet
General Idea:
(i) Assign variable for the unknown that we need to find
(ii) Sketch a diagram to help us visualize the problem
(iii) Write the mathematical equation representing the description given.
(iv) Solve the equation by substitution method. Solving means finding the values of the variables which will make both the equation TRUE
Applying the concept:
Given: x represents the length of the pen and y represents the area of the doghouse
<u>Statement 1: </u>"The pen is 3 feet wider than it is long"

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<u>Statement 2: "He also built a doghouse to put in the pen which has a perimeter that is equal to the area of its base"</u>

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<u>Statement 3: "After putting the doghouse in the pen, he calculates that the dog will have 178 square feet of space to run around inside the pen."</u>

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<u>Statement 4: "The perimeter of the pen is 3 times greater than the perimeter of the doghouse."</u>

Conclusion:
The systems of equations that can be used to determine the length and width of the pen and the area of the doghouse is given in Option B.

<span>1. $119 2. 64 beads 3. 4 candles 4</span>
3x^2 * 4x^3 = 12x^5
Answer is degree 5
The formula for the volume of a rectangular solid is V = L*W*H
Multiply out the length, width and height given: 40*10*5 = 400*5 = 2000
The volume is 2,000 cubic centimeters