Answer: 
Step-by-step explanation:
The first thing you must remember is the mulplication of signs. You know that:
You can observe that the number inside the parentheses is positive (+) and the sign that is outside the parentheses is negative (-), therefore, when you multiply these signs you get a negative sign (-). Then you get:
Now, you need to add these numbers. And the result obtained is:
Answer:
108
Step-by-step explanation:
triangles of the sides 3×4=12
5×8=40
4×8=32
3×8=24
add everything
If a triangle has sides of 7 cm and it is an equilateral you can draw a line right down the middle to form two congruent triangles.
These smaller triangles have a hypotenuse of 7cm and a base of 3.5 cm (7/2)
To work out the height, use Pythagoras’ theorem.
a^2 + b^2 = c^2 where c is the hypotenuse and a and b are the other two sides
7^2 - 3.5^2 = 36.75
Square root answer
= 6.06 cm
That’s the height of the triangle
Area of a triangle is base x height divided by 2
So 7 x 6.06 = 42.43…
/2
= 21.2 cm^2 to one d.p
Hope this helped!
Please mark Brainliest!!
Answer:
1. 280/11
2. 1700/11
3. 280/11
4. 3600
5. 360
Step-by-step explanation:
Let n = sides of a regular polygon
For these problems, n = 22 because there are 22 sides.
I am going to write the formulas needed for each question below.
- 360/n
- 180 - 360/n
- 360/n
- 180(n-2)
- 360 (isn't affected by n)
To solve, just plug in N with 22.
These formulas are very easy to prove and I recommend if you have time try to prove these.
or 
At the point/angle E:
- the adjacent side(side <u>next to</u> the point/angle) is ED
- the opposite side(side of the triangle <u>across</u> from the point/angle) is DF
- the hypotenuse (the<u> longest side</u> of the triangle) is EF.
sin ∠E = 
sin ∠E = 
(simplified)
