Question

What is the equation of a line with slope -1/2 passing through (-5,4)?

Answer 1

For this question you need to use what's called point-slope form. It's named this way because you can use it if you have both the slope and a point at which the line passes through. That said, the equation is as follows:

y - y1 = m(x - x1)

Both y1 and x1 represent the y and x coordinates you are given in the question. Also, m represents the slope of the line that you are given. Knowing this, our equation now looks like this:

y - 4 = -0.5(x - (-5))

And now simplify:

y - 4 = -0.5(x + 5)
y - 4 = -0.5x - 2.5

y = -0.5x + 1.5