How would I graph 5x+3y=-15? How would I graph 8x+2y=-4? Is the x=8/-3 the x-intercept for the equation -3x+4y=8?

Saturday, August 27, 2016

How would I graph 5x+3y=-15? How would I graph 8x+2y=-4? Is the x=8/-3 the x-intercept for the equation -3x+4y=8?

One method to graph is to find the x and y intercept of the equation. Then use the intercepts to graph the line.

Example 1: $\displaystyle{5}{x}+{3}{y}=-{15}$

To find the x-intercept of the linear equation let y=0 and solve for the x value.

$\displaystyle{5}{x}+{3}{y}=-{15}$

$\displaystyle{5}{x}+{3}{\left({0}\right)}=-{15}$

$\displaystyle{5}{x}=-{15}$

x=-3

Therefore one point on the line is the coordinate (-3, 0).

To find the y=intercept of the linear equation let x=0 and solve for the y value.

$\displaystyle{5}{x}+{3}{y}=-{15}$

$\displaystyle{5}{\left({0}\right)}+{3}{y}=-{15}$

$\displaystyle{3}{y}=-{15}$

$\displaystyle{y}=-{5}$

Therefore a second point on the line is the coordinate (0, -5).

Plot the points (-3, 0) and (0, -5) and draw a line through the two points.

The same method can be used for the second example.

Example 2: $\displaystyle{8}{x}+{2}{y}=-{4}$

To find the x-intercept of the linear equation let y=0 and solve for the x value.

$\displaystyle{8}{x}+{2}{y}=-{4}$

$\displaystyle{8}{x}+{2}{\left({0}\right)}=-{4}$

$\displaystyle{8}{x}=-{4}$

$\displaystyle{x}=-\frac{{1}}{{2}}$

Therefore one point on the line is the coordinate (-1/2, 0).

To find the y=intercept of the linear equation let x=0 and solve for the y value.

$\displaystyle{8}{x}+{2}{y}=-{4}$

$\displaystyle{8}{\left({0}\right)}+{2}{y}=-{4}$

$\displaystyle{2}{y}=-{4}$

$\displaystyle{y}=-{2}$

Therefore a second point on the line is the coordinate (0, -2). Plot the points (-1/2, 0) and (0, -2) and draw a line through the two points.

Example 3: $\displaystyle-{3}{x}+{4}{y}={8}$

To find the x-intercept of the linear equation let y=0 and solve for the x value.

$\displaystyle-{3}{x}+{4}{y}={8}$

$\displaystyle-{3}{x}+{4}{\left({0}\right)}={8}$

$\displaystyle-{3}{x}={8}$

$\displaystyle{x}=-\frac{{8}}{{3}}$

Therefore one point on the line is the coordinate (-8/3, 0). To find the y=intercept of the linear equation let x=0 and solve for the y value.

$\displaystyle-{3}{x}+{4}{y}={8}$

$\displaystyle-{3}{\left({0}\right)}+{4}{y}={8}$

$\displaystyle{4}{y}={8}$

$\displaystyle{y}={2}$

Therefore a second point on the line is the coordinate (0, 2). Plot the points (-8/3, 0) and (0, 2) and draw a line through the two points.

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)