The variables x and y vary inversely. when y is 725, x is 20. what is x when y is 50?

A

Step-by-step explanation:

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Rearrange:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

                    y-(5*x-25)=0

STEP

1

:

Equation of a Straight Line

1.1     Solve   y-5x+25  = 0

Tiger recognizes that we have here an equation of a straight line. Such an equation is usually written y=mx+b ("y=mx+c" in the UK).

"y=mx+b" is the formula of a straight line drawn on Cartesian coordinate system in which "y" is the vertical axis and "x" the horizontal axis.

In this formula :

y tells us how far up the line goes

x tells us how far along

m is the Slope or Gradient i.e. how steep the line is

b is the Y-intercept i.e. where the line crosses the Y axis

The X and Y intercepts and the Slope are called the line properties. We shall now graph the line  y-5x+25  = 0 and calculate its properties

Calculate the Y-Intercept :

Notice that when x = 0 the value of y is -25/1 so this line "cuts" the y axis at y=-25.00000

 y-intercept = -25/1  = -25.00000

Calculate the X-Intercept :

When y = 0 the value of x is 5/1 Our line therefore "cuts" the x axis at x= 5.00000

 x-intercept = 25/5  =  5

Calculate the Slope :

Slope is defined as the change in y divided by the change in x. We note that for x=0, the value of y is -25.000 and for x=2.000, the value of y is -15.000. So, for a change of 2.000 in x (The change in x is sometimes referred to as "RUN") we get a change of -15.000 - (-25.000) = 10.000 in y. (The change in y is sometimes referred to as "RISE" and the Slope is m = RISE / RUN)

   Slope     = 10.000/2.000 =  5.000

Geometric figure: Straight Line

 Slope = 10.000/2.000 = 5.000

 x-intercept = 25/5 = 5

 y-intercept = -25/1 = -25.00000