# I need help with this math question!!!!!!!?

+1 vote

So I have a test tomorrow and I need some help to reduce the confusion. The lesson is "Solving linear systems with graphing" and the math problem is two equations.
Equation 1: x-y=2
Equation 2: x+y=-8
they call it the graph and check method.
Can you list the steps?
Extra problems with numbers and not variables only.

+1 vote

1: x -y  = 2

2: x+ y = -8

Therefore 2x + 0y =-6

2x = -6

x = -3

Substitute  x = - 3 in the  second equation

Therefore -3 + y =- 8

0 + y =  -8 +3

y = -5

The intercept point is (-3, -5)

The graph is

The system of equations are x - y = 2 and x + y = - 8.

Slope - intercept form of the line equation is y = mx + b, where, m is slope and b is y - intercept.

First write the equations in slope - intercept form.

The first equation is x - y = 2.

y = x -  2.

Compare the equation with slope - intercept form : y = mx + b.

slope = 1 and y - intercept is - 2.

y - intercept is - 2, so the line crosses the y - axis at (0, - 2).

Using slope find the next point.

Slope = rise/run = 1/1

Start at point (0, - 2), move 1 unit up and 1 unit right, then plot the point (1, - 1).

The second equation is x + y = - 8.

y = - x - 8.

Compare the equation with slope - intercept form : y = mx + b.

slope = - 1 and y - intercept is - 8.

y - intercept is - 8, so the line crosses the y - axis at (0, - 8)

Using slope find the next point.

Slope = rise/run = - 1/1

Start at point (0, - 8), move 1 unit down and 1 unit right, then plot the point (1, - 7).

Draw the lines through these points.

Graph :

Observe the graph,

The solution of the system (x, y) = (- 3, - 5).