Question

What is an equation of the line that passes through the points (4,-2) and (8,-7)?

Answer 1

the slope-intercept form for any line is y = mx + b, where m is the slope and b is the y-intercept.

now, let's calculate the slope:

=

here is the equation we currently have solved: y = x + b

now we have to solve for the y-intercept. to do this, we substitute one of the given points into the equation, and solve for b.

let's use (8, 2). in this ordered pair, the 8 is the x, and the 2 is the y.

2 = 8 + b

2 - 8 = b

b = -6

and now we have our final equation!

y = x - 6

hope this helped! please let me know if you are confused about anything i did smiley

Explanation:

Answer 2

• y = -5/4x + 3

Explanation:

Find the slope first:

• m = (y2 - y1)/ (2 - x1)
• m = (-7 + 2)/(8 - 4) = -5/4

Use point-slope form and the coordinates of one of the points:

• y - y1 = m(x - x1)
• y - (-2) = -5/4(x - 4)
• y + 2 = - 5/4x + 5
• y = -5/4x + 3