The rule for regular polygons are very easy. The number of reflectional symmetries is same as the number of sides. Regular polygons have all sides the same length and all angles same. Reflection symmetry means that you can fold the shape along that line and it will match up.
For this question, we want the number of reflectional symmetries of a regular decagon. Decagon is a 10 sided figure. Hence, the number of reflectional symmetries is 10.
There are 5 symmetry lines from one vertex to opposite vertex and 5 more symmetry lines form midpoint of one side to midpoint of opposite side.
ANSWER: 10
Answer:
C. x=3 and y=−6
Step-by-step explanation:
Step: Solvex−2y=15for x:
x−2y=15
x−2y+2y=15+2y(Add 2y to both sides)
x=2y+15
Step: Substitute2y+15forxin2x+4y=−18:
2x+4y=−18
2(2y+15)+4y=−18
8y+30=−18(Simplify both sides of the equation)
8y+30+−30=−18+−30(Add -30 to both sides)
8y=−48
8y8=−488(Divide both sides by 8)
y=−6
Step: Substitute−6foryinx=2y+15:
x=2y+15
x=(2)(−6)+15
x=3(Simplify both sides of the equation)
Answer:
x=3 and y=−6
A) Because the 80 is by itself that would be the start up fee.
B) We are told x is the number of months. Since the X is being multiplied by 30, we know that would be the total monthly cost. This is being added to the 80, which does not have an exponent, so we know this is a single cost, which would be the start up fee.
C) Copying the same format as the given equation above, change the numbers:
f(x) = 20 + 35x
D) I used the same format as the first equation, which meant replacing the start up cost from the original one ( 80) with the start up of the new one (20). Then I changed the monthly cost from the original one (30) with the monthly cost of the new one (35).
E) Replace x in each equation with 8 and calculate the cost of each:
80 + 30(8) = 80 + 240 = $320
20 + 35(8) = 20 + 280 = $300
The second club (club B) is the cheaper option for her.
Answer:
Use this formula for these kinda things.
Step-by-step explanation:
Remember The z is the hypathonous, it means the biggest side.

where Z is going to be C
put this all together

put it into calculator, means 373=

therfore take the square root, it will be

which it will be 19.31
2*2+4*2(1+1) that is going be your answer