How to solve 5x - 4y = -20

Question

I have to make this plottable on a graph and I don't know how to do that.

Answer 1

What you first need to do is get it into a general form of y = ax + b. So you need to get y on the left side by itself. Subtract 5x from both sides to get -4y = 2 - 5x. Next divide both sides by -4 to get y = (2 - 5x)/(-4) or y = (5/4)x - (1/2). Now to plot the line on a graph, pick a point for x then find out the value for y. I recommend starting with simple numbers like x = 0, x = 1, etc. If x = 0, then y = (5/4)(0) - (1/2), or y = -1/2. So the first point on the graph would be (0, -1/2). Plot a few more points then draw the line.

Answer 2

Here are the steps to do that:

1. Get the equation in this format (y-intercept format): Y = M(X) + B
2. Where M is the slope and B is the y intercept
3. Starting with the y intercept (B), put a dot, then use the slope (rise/run) to get the second dot
4. Connect the dots for the line.

5X - 4Y = -20

1. Subtract 5X from both sides: -4Y = -5X - 20; Then divide by -4 both sides: Y = (5/4)X + 5
2. Dot at (0,5), the y intercept; stay there and use rise/run for the slope (rise 5, run 4) to get the second dot at (4,10)
3. Connect those 2 dots for the line.

Answer 3

5x - 4y = -20

5x + 20 - 4y = 0

5x+20 = 4y

(5/4)x + 5 = y

M=5/4 and B=5

plot point (0,5)....

go up 5 and 4 to the right, so plots ( 4,10)

go up 5 and 4 to the right again, so plots ( 8,15)

here is the X vs Y table:

X Y

0 5

4 10

8 15

12 20

-4 0

note that 0 = (5/4)x + 5

-5 = (5/4)x

(4/5)(-5) = x

-4 = x

Answer 4

With 2 variables and one equation there is no unique solution.

To plot it: select a set of values for x and from the equation calculate the values for y.

This gives you a set of points to plot on graph paper. Your graph should be a straight line.