At the end of the day, Mr. Díaz drains the pool. The equation
y = -50x + 300 can be used to find y, the number of gallons of
water left after draining the pool for x minutes. Graph the
equation. How long does it take to drain the pool? Explain.

Respuesta :

Answer: 6 minutes.

Step-by-step explanation: You can use a graphing calculator to see the exact graph, but you're trying to figure out what value of x gives you a y of 0. -50 times 6 is 300, plus 300 equals 0.

The graph of the equation y = -50x + 300 is a straight line, and plotted below. The time it take the pool to drain, according to this equation, is  6 minutes.

How do we make graph of a function?

Suppose the considered function whose graph is to be made is f(x)

The values of 'x' (also called input variable, or independent variable) are usually plotted on horizontal axis, and the output values f(x) are plotted on the vertical axis.

They are together plotted on the point

(x,y) = (x, f(x))

This is why we usually write the functions as:

y = f(x)

For this case, we're specified that:

  • y = the number of gallons of water left after draining the pool for x minutes.
  • The relationship between x and y given is: y = -50x + 300

Take two different values of x, let it be 0 and 1.

Then, the value of y we get is:

  • Case 1: x = 0:

[tex]y = -50x + 300\\y = -50 \times 0 + 300\\y = 300[/tex]

Thus, one point on the equation y = -50x + 300 is (0,300)

  • Case 2: x = 1:

[tex]y = -50x + 300\\y = -50 \times 1 + 300\\y = 300 - 50 = 250[/tex]

Thus, another point on the equation y = -50x + 300 is (1,250)

Plot these points taking x on horizontal and y on vertical axis. Then join those two points by a straight line. This is the graph of the considered equation as equation of type [tex]y = mx +c[/tex] is a straight line's equation and for straight line, two of its points are sufficient to plot it.

The graph is given below.

Since we know that:

y = number of gallons of water left after draining the pool for x minutes,

so when the pool drains of fully, there will be no water left, or y = 0.

Putting y = 0 in the equation y = -50x + 300, we get:

[tex]y = -50x + 300\\0 = -50x + 300\\\\\text{Adding 50x on both the sides}\\\\50x = 300\\\\\text{Dividing both the sides by 50}\\\\x = \dfrac{300}{50}= 6[/tex]

Thus, when y= 0, we get x = 6, so when the fully filled pool is drained for 6 minutes, the whole pool gets drained (for this case).

Thus, the time it take the pool to drain, according to this equation, is  6 minutes. The graph of the equation y = -50x + 300 is given below.

Learn more about graphing functions here:

https://brainly.com/question/14455421

#SPJ2

Ver imagen astha8579