Question 40553
m = -7, passing through (7,5)

The "slope-intercept form" means that the main information we need in this equation is the values for the slope and the value for the y-intercept.  The y-intercept is the point at which the line crosses or hits the y-axis.  The y-intercept is indicated by the points (0, b) in which the x value is always zero and the y value is a real number value.

The slope-intercept form is:
y = mx + b

The value for each variable is:
y = the y value of a point
m = the slope (y - y)/(x - x)
x= is the x value of the same point
b = the y-intercept (0, b)

To find the slope-intercept form for:  m = -7, passing through (7,5)
 
First substitute the values into the y = mx + b equation:

5 = -7(7) + b

Solve for "b"

5 = -49 + b
5 + 49 = -49 + 49 + b
54 = b

Going back to the explaination of y = mx + b, determine which terms represent "m" for the slope and which terms equal "b" for the y-intercept.  The answer is the slope "m" is represented by -7.  The y-intercept is represented by 54.

Plug the value for the slope "m" and for the y-intercept "b" back into the slope-intercept formula:

y = -7x + 54