Answer:
126 units
Step-by-step explanation:
Ed=9 units,Ab= 81 units, Ec=x and AC=140
Given:
The coordinates of ∆ABC are A(-3, 2), B(5, 8) & C(11, 0).
To find:
The type of the given triangle.
Solution:
Distance formula:

Using the distance formula, we get





Similarly,





And,





Two sides of the triangle are equal, i.e.,
. So, the triangle is an isosceles triangle.
Sum of square of two smaller side is




Using the Pythagoras theorem, we can say that the given triangle is a right triangle.
Therefore, the correct options are B and F.
Answer:
The angle of elevation is approximately 
Step-by-step explanation:
Notice that the two pieces of information given: "400 ft away from a building", and building that is "850 ft tall", can be regarded as the two legs of a right angle triangle (see attached image).
Then the angle
that we are trying to find (the angle of elevation) can be found by using the arc-tangent function:

The slope formula can be used to prove a triangle has a right angle