Answer:
By the angles and sides, but if you need more help here is a link to a video that could be pretty helpful.
Step-by-step explanation:
https://www.khanacademy.org/math/cc-fourth-grade-math/plane-figures/imp-classifying-triangles/v/scalene-isosceles-equilateral-acute-right-obtuse#:~:text=Learn%20to%20categorize%20triangles%20as,acute%2C%20right%2C%20or%20obtuse.
B and C since in these cases money is leaving your account.
This is how I would go about solving this, hope it helps.
Answer:
Value of 
Step-by-step explanation:
The given triangle is isosceles
Here
An equilateral triangle has all side lengths the same, and all angles are 60 degrees. Using this we can split the triangle along its altitude to get two right triangles with a hypotenuse of length 10 and a base of 1/2 of the original length, so 5. Now we can either use the Pythagorean theorem (a^2+b^2=c^2) or the fact that it is a 30 60 90 triangle (angles measure at 30 60 and 90 degrees) Pythagorean theorem is probably easier.
It stated that the squares of the two legs of a right triangle add to the square of the hypotenuse. So a(the altitude)^2+5(the base)^2=10(the hypotenuse)^2
A^2+5^2=10^2
A^2+25=100
A^2=75
A=sqrt(75)
A=5*sqrt(3)
Final answer:
The altitude of an equilateral triangle with side length 10 is 5sqrt(3), or about 8.66
