Answer:
See below.
Step-by-step explanation:
By definition the median of the triangle bisects the base of the isosceles triangle.
We need to prove that the 2 triangles formed by the median are congruent.
If the 2 triangles are ABD and ACD where BD is the median and < ABC is the angle from which BD is drawn.
BD = BD ( the common side)
AD = DC ( because BD is the median).
AB = AC ( because ABC is an isosceles triangle).
So Triangles ABD and ACD are congruent by SSS.
Therefore m < ABD = m < CBD, so BD is the bisector of < ABC.
To prove BD is also the altitude:
Triangles ABD and CBD are congruent as we have just proven. Therefore the
of measure of the base angle ABD = m < CBD . Also they are adjacent angles ( on the same line) so they add up to 180.
Therefore angles ABD and CBD are both right angles and BD is the altitude of triangle ABC.
Answer:
200.1625
Step-by-step explanation:
38.15 × 4 + .125 × 380.5
Example: 
We can see that there is more than one number with the variable x, therefore, we say they're ''like terms'' and because of that they can be summed. We do this with all of the other numbers with similar variables. If no numbers with similar variables are left, like 4a, you don't do anything but write them as they are. You can also see that 8 and 9 can also be summed because neither of them has a variable, therefore they're similar.
In this step, you just do the operation with the numbers and keep the same variable.


since there are not more numbers similar in variables, this operation is done.

Answer:
<h3> 10,450</h3>
Step-by-step explanation:
21-13=8 and 29-21=8
So this is aritmetic series where a₁ = 13, and r = 8
Sum of the first n terms:
