Question

Write an equation of the line that passes through the given points.
(-1,5) and (2,-7)

The equation is ___.

Here's what, I did:

Slope = rise/run = y2 - y1/ x2 - x1, where x2 - x1 # 0

Substitute the coordinates of the points into this formula and simplify.

slope = -7 -5/2-(-1)
= 3

Then use the slope and the coordinates of one of the points to find N. For this problem, use the slope and the first given point.
y = mx + B
5 = 3(-1) + b
4 = B

Finally, substitute the slope and y intercept into the slope intercept form.
y = mx + b
y = 3x + 5

Therefore the answer is y= 3x + 5

Please correct me if this is wrong.

Answer 1

clearly you did not check your answer. The two points must be on the line.
(-1,5): does 3(-1) + 5 = 5? No❌
(2,-7): does 3(2)-5 = -7? No ❌

You say slope = -7 -5/2-(-1) = 3
But slope = (-7 -5)/(2-(-1)) = -12/3 = -4
So you know y = -4x + b
Now use one of the points to find b.

Answer 2

I don't understand