Answer: 81 units²
Step-by-step explanation: To solve this problem, remember that the formula for the area of a square is 4s.
Therefore, since the perimeter of the given square is 36, we have 36 = 4s and dividing both sides by 4, 9 = s.
Now, remember that the formula for the area of a square is s² and since the length of a side of the given square is 9, we have (9)² or 81.
So the area of a square that has a perimeter of 36 is 81 units².
Answer:
See below
Step-by-step explanation:
You know that he spent 1/3 of his earnings, and then 1/4. After this, he has $28.90. You can write the equation like this:
1/4(x * 1/3) = $28.90.
If you need to solve it:
1/4 * 1/3x = 28.90
1/12x = 28.90
x = 346.80
Answer:
The population of this city in 13 years is 440,550.
Step-by-step explanation:
Given:
Suppose a city with population 300, 000 has been growing at a rate of 3% per year.
Now, to find the population of this city in 13 years.
Let the population of this city in 13 years be 
Population (
) = 300,000.
Rate per year (
) = 3%.
Time (
) = 13 years.
Now, we put formula to get the population of the city in 13 years:

Therefore, the population of this city in 13 years is 440,550.
Answer:
Since r is the distance from the origin to (x,y), it is the magnitude r=√x2+y2. Alternatively, from the equation (1), one can calculate directly that x2+y2=r2cos2θ+r2sin2θ=r2(cos2θ+sin2θ)=r2.
Step-by-step explanation: