Question

Can you help me with Relations and function in Algebra

Answer 1

Use the following slope-intercept form of a line equation:

y = mx + b

Where m is the slope of the line and b the value of y when x=0 (it is also the y-intercept).

To find the slope m, use the following formula:

`m=(y_2-y_1)/(x_2-x_1)`

where (x1,y1) and (x2,y2) are any pair of points on the line.

For instance, use:

(x1,y1) = (-4,-8)

(x2,y2) = (8,4)

`m=(4-(-8))/(8-(-4))=(4+8)/(8+4)=(12)/(12)=1`

You can notice, based on the graph, that y = -4 for x = 0. Then, the y-intercept is b = -4.

Then, by replacing the values of m and b into the slope-intercept formula, you get:

y = x - 4 (this equation represents the line)