Answer:
20,000
Step-by-step explanation:
20,000 is already rounded to the nearest ten given the tenths place is equal to 0.
Answer: 
Step-by-step explanation:
By definition, an Isosceles triangle has two equal sides and its opposite angles are congruent.
Observe the figure attached, where the isosceles triangle is divided into two equal right triangles.
So, in this case you need to use the following Trigonometric Identity:

In this case, you can identify that:

Substituting values, and solving for "x", you get:

Therefore, the length of BC rounded to nearest tenth, is:

Simply remember PEMDAS:
P = Parentheses
E = Exponents
M = Multiplication
D = Division
A = Addition
S = Subtraction
You perform these actions from left to right.
However in this case it is not possible for it to equal 60.
Your hypothesis is correct because you substitute 1 to x then add which gives you an answer
Answer: 5=5
Your octagon has a central angle of 360 deg. Since you're speaking of an octagon, which implies that the octagon is made up of eight triangles, divide 360 deg by 8 to obtain the measure of each minor arc formed.