180° rotation about the origin changes the signs of the coordinates.
(x, y) → (-x, -y)
It is a reflection over the y-axis and a reflection over the x-axis (in either order).
<em>You did not provide the options so hopefully you can figure out the answer based on the information I provided.</em>
The measure would be 20 since five times four is 20
For slope, people sometimes use the description 'rise divided by run'. We know that the y axis describes rise, and the x axis describes run. So rise divided by run written numerically is 
. Now let's look at the line above. We can see that every time the y value goes up one unit, the x value goes right two units. This means that [tex]\frac{y}{x} --> \frac{y + 1}{x + 2}
This can be rewritten as 1/2, so the is 1/2. Hope this helped.
