Question

which equation of a line is shown on the graph? (-1, +1) a. y=x+1 b. x+y=1

Answer 1

Given lines are y = x+1 and x+y = 1

Graph of the two lines

Draw the coordinate plane.

plot the two lines.

plot the point (-1,1).

Observe the graph,from the graph no given line equation is not shown the given point (-1,1).

Substitute (x,y) = (-1,1) in above gven equations.

---> y = x+1

-1 = 1+1

-1 = 2

---> x+y = 1

-1+1 = 1

0 = 1

(-1,1) is not satisify the above equations.

(-1,1) is not intersecting point of each of them.

Answer 2

Substitute (x,y ) = (-1,1) in above equations.

---> y = x + 1

-1 = 1+1

-1 = 2

---> x + y = 1

-1 + 1 = 1

0 = 1

(-1,1) is not satisfy the above equations.

(-1,1) is not intersecting point of each of them.

First line  y = x  + 1

The equation is in already slope-intercept form y = mx + b, where m  is slope and b  is y -intercept.

slope = 1 and y -intercept is 1.

y -intercept is 1, so the line crosses the y -axis at (0, 1)

Using slope find the next point.

Slope = rise/run = 1

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

Draw a line through these points.

Now  the second line x + y  = 1

y  = - x + 1

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

slope = -1 and y -intercept is 1.

y -intercept is 1, so the line crosses the y -axis at (0, 1)

Using slope find the next point.

Slope = rise/run = -1

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

Draw a line through these points.

Now plot the point (-1,1).

Graph :

From the graph,observe the  (-1,1) is not a solution to the system ,because it is not on either line.