Answer:
3.8m
Step-by-step explanation:
Since Lara is putting lace trim around the border of a circular tablecloth, by the time she finishes she has covered the circumference.
The circumference of a circle is calculated using:

where d is the diameter of the circle.
It was given that the diameter of the circular table cloth is 1.2 meters.


Therefore the length of the lace she needed is 3.8m
The answer to the question is the first, third and fifth
1. Divide wire b in parts x and b-x.
2. Bend the b-x piece to form a triangle with side (b-x)/3
There are many ways to find the area of the equilateral triangle. One is by the formula A=

A=

Another way is apply the formula A=1/2*base*altitude,
where the altitude can be found by applying the pythagorean theorem on the triangle with hypothenuse (b-x)/3 and side (b-x)/6
3. Let x be the circumference of the circle.

so

Area of circle =

4. Let f(x)=

be the function of the sum of the areas of the triangle and circle.
5. f(x) is a minimum means f'(x)=0
f'(x)=

=0



6. So one part is

and the other part is b-
Answer:
ok I will help
Step-by-step explanation: