To draw a graph on a calculator, first press the Y= button and type the function in one of the rows. Having written the function, you can push GRAPH to draw it. In our case, you should replace A and L with x and y, respectively.
B
b
To find the areas that can be watered by the given pipes, substitute the given lengths in the equation. Then solve the equation for A.
A
a
Domain:
B
b
18.03 yd^2, 46.16 yd^2, and 121.89 yd^2
Practice makes perfect
a
To draw a graph on a calculator, we first press the Y= button and type the function in one of the rows. Having written the function, we can push GRAPH to draw it. In our case, we will replace A and L with x and y, respectively.
Because the sprinkler can water between 1 and 130 square yards of lawn, we should restrict the domain between 1≤ x ≤ 130.To do that we will press 2nd and MATH. Then, we will use the fourth option and sixth option in the TEST column and first option in the LOGIC column.
With this, the domain can be restricted as shown below.
To see the graph properly, we can set the viewing window as shown below.
b
To find the area that can be watered if the length of the pipe is 500 inches long, we will substitute L=500 in the given equation and solve it for A.
The area of the lawn that can be watered is about 18.03 square yards. Proceeding in the same way, we can find the area of the lawn that can be watered if the length of the pipe is 800 or 1300 inches long.
