Answer:
y = -2 + 5
Step-by-step explanation:
To find the equation of a line when you only have two points you need to use the slope formula (y 2 -y 1) over (x 2 -x 1) Any set of points can be y 2, and x 2, just as long as you only use the ones in the same parenthesis as those values. I will use the points in A: (-1, 7) as my y2 and x2 values and my points B: (1, 3) as my y 1 and x 1 values. (7-3) over (-1-1) this gives me 4 over -2. Then I will solve out to get my slope by dividing 4 by negative 2. This gives me that the slope of this line will be -2. Now, we need to find the y intercept. We get this by plugging in one of the sets of coordinates in for x and y in your half completed equation. So far we have y=-2x+b (b stands for y intercept) If we plug in the coordinates from coordinates B (1, 3), our equation looks like 3=-2(1)+b. Now, we solve this equation to find the y-intercept so we can complete the equation. First, multiply negative 2 by 1, you will get 3 equals -2 +b. Then add the two to both sides to cancel it out. Then you get that the y-intercept equals 5.
Now you have all the pieces you need for your equation using standard form: y=mx+b. Plug in your slope for m, and the y intercept for b. You get: y equals -2 plus 5.
Hope your day gets better :)
