The answer is B. (15,18)
Solution:
First, let's set the variables first.
X = dollars per hour to clean the floor
Y = dollars per hour to clean the rest of the house
For the first statement, "<span>2 hours to clean floors and 3 hours to clean the rest of a house, the total charge is $84"
We can put it into an equation.
2X + 3Y = 84 </span>⇒ equation 1
For the first statement, "<span>1 hour to clean floors and 4 hours to clean the rest of a house, the total charge is $87'
X + 4Y = 87 </span>⇒ equation 2
Multiply first equation 2 by 2 to make the coefficient of both equations 1 and 2 the same.
Using elimination method in solving for x and y,
(equation 1) 2X + 3Y = 84
(equation 2) 2(X + 4Y) = 87
2X + 8Y = 174 ⇒ equation 3
Next, subtract equation 3 from equation 1.
2X + 3Y = 84
- (2X + 8Y = 174)
-------------------------
- 5Y = -90
Y = 18
Find X when Y = 18
@ equation 1 : 2X + 3Y = 84
2X + 3(18) = 84
2X + 54 = 84
2X = 84 - 54
2X = 30
X = 15
The answer is in ordered pairs of cleaning the floors and to clean the rest of the house. So, in the form (X,Y).
Answer: (15,18)
Because the formula for the area of a rectangle is length times width, all you have to do is multiply 15 by 15 and it should get you 225 as your answer
For this case we have the following expression:

Multiplying we have:

We round the expression and we have that it is equivalent to: 20.
Thus,
is approximately equal to 20.
Answer:
The expression given is approximately equal to 20.
Option C
Answer:
8.29
Step-by-step explanation:
degrees of sector / by 360 * by pi* r^2
Answer:
A x>9
Step-by-step explanation:
add 4 to both sides and ta da