Answer:
d is the answer
Step-by-step explanation:
perimeter of rect = 2(7+3) = 20
perimeter of square = 4 a =20
a = 5
Answer:
a) 
b) 
c) term number 17 is the one that gives a value of 40
Step-by-step explanation:
a)
The sequence seems to be arithmetic, and with common difference d = 3.
Notice that when you add 3 units to the first term (-80, you get :
-8 + 3 = -5
and then -5 + 3 = -2 which is the third term.
Then, we can use the general form for the nth term of an arithmetic sequence to find its simplified form:

That in our case would give:

b)
Therefore, the term number 20 can be calculated from it:

c) in order to find which term renders 20, we use the general form we found in step a):

so term number 17 is the one that renders a value of 40
Answer:
Area of the regular dodecagon inscribed in a circle will be 27 square units.
Step-by-step explanation:
A regular dodecagon is the structure has twelve sides and 12 isosceles triangles inscribed in a circle as shown in the figure attached.
Since angle formed at the center by a polygon = 
Therefore, angle at the center of a dodecagon =
= 30°
Since one of it's vertex is (3, 0) therefore, one side of the triangle formed or radius of the circle = 3 units
Now area of a small triangle = 
where a and b are the sides of the triangle and θ is the angle between them.
Now area of the small triangle = 
= 
Area of dodecagon = 12×area of the small triangle
= 12×
= 27 unit²
Therefore, area of the regular octagon is 27 square unit.
Answer:
a)
+8x+15
b)
-x-20
Step-by-step explanation:
a) (x+3)(x+5)
a)
+5x+3x+15
a)
+8x+15
b) (x+4)(x-5)
b)
-5x+4x-20
b)
-x-20