When the X term is one, and doesn't have a leading coefficient, then you can factor it using the box and diamond method. look up videos on Khan Academy of the box and diamond method for solving trinomials. For number 9, you have a difference of squares. That means you can factor to just 2 terms. (x+4)(x-4) this works because 16 has an easy square root, and the sign in between is a negative(difference)
First we are going to draw the triangle using the given coordinates. Next, we are going to use the distance formula to find the sides of our triangle. Distance formula:
Distance from point A to point B:
Distance from point A to point C:
Distance from point B from point C
Now, we are going to find the semi-perimeter of our triangle using the semi-perimeter formula:
Finally, to find the area of our triangle, we are going to use Heron's formula:
We can conclude that the perimeter of our triangle is 140.13 square units.