Question

Write an equation in slope intercept form that passes through the points ( 3,9) and (4,6)

Answer 1

Hello!

To write this equation, let's first find the slope using the formula $\frac{y_{2} - y_{1} }{x_{2} - x_{1}}$. 

Plug in the values

$\frac{6 - 9}{4 - 3}$

Now solve to find our slope.

$\frac{6 - 9}{4 - 3} = \frac{-3}{1}$

<u />Your slope is -3.

Plug that into slope-intercept equation.

$y = -3x + b$

Now we find our y-intercept by plugging in a y-coordinate for the y value in the equation. I'll use 6

$4 = -3x + 6 6 = -3(4) + b 6 = -12 + b 6/6 = -12/6 + b -2 = b$

Your y-intercept is -2.

Your equation is y = -3x - 2