If this is an equilateral triangle, we need half of it to find the height which is a leg of a right triangle with a hypotenuse of 15. That means that the base of this half triangle is 7.5. Use Pythagorean's Theorem to fine the height.

. x = 12.99 or 13
To find the height of the TV you first need to realize that the question is giving you dimensions for a triangle.
Every triangle has a hypotenuse and two sides. To find the hypotenuse you square both sides, add them, and then square root. So to find one of the sides you get the hypotenuse, square it, and subtract the square length of the given side.
The equation is 25^2-20^2.
Which if simplified is 625-400, the then solution is going to be 225.
You next will square root 225, 225^(1/2). Which your answer should be 15 inches for the missing side length.
Answer:
-1/6
Step-by-step explanation:
(10 - 8)/(-21 + 9)= 12/-12= -1
y - 8 = -1(x + 9)
y - 8 = -x - 9
y = -x - 1