Question

How do you graph the equation 5x + y = 4 by plotting points.

Answer 1

Hint: Now to graph the given equation we will first find the solution points to the equation. To do so we will write y in terms of x. now we will substitute different values of x and find the corresponding value of y. Hence we get the solution (x, y) of the equation. Now we will plot the points on the graph and draw a line passing through the points. Hence we have the graph of the given equation.

Complete step by step solution:
Now consider the given equation 5x + y = 4.
Now to draw the graph of the equation we will first need the values (x, y) which satisfies the equation.
Now to find the solution let us first rewrite the equation as y = 4 – 5x.
Now on substituting the values of x we get a different solution of y.
Let us first substitute x = 0.
Hence we get the value of y as y = 4.
Hence we get (0, 4) s a solution to the given equation.
Now let us substitute x = 1.
Hence we get y = 4 – 5(1) = - 1
Hence (1, -1) is also the solution to the equation.
Now let us substitute x = - 1.
Hence we get y = 4 – 5(-1) = 9.
Hence (-1, 9) is also the solution to the equation.
Now we have three solutions to the equation which are (0, 4), (1, -1) and (-1, 9).
Hence we will plot the points on the graph.
Now the equation of line 5x + y = 4 is nothing but the line passing through the four points.
Hence we get the graph as,

Note:
Now note that when we substitute x = 0 we get a point on y axis and this point is called the y intercept. Similarly if we substitute y = 0 then we get a point on the x axis and is called the x intercept. Also note that while taking points we get integer values of y so it is easy to plot.