Area of a semicircle is 1/2* πr^2
Area of a square is s^2
Square’s area: 4mm^2
The radius is 3mm
Plug into the equation
1/2* π(3^2)
1/2* π(9)
We can use 3.14 as an estimate of pi
1/2*28.26
14.13mm^2
Now just add them both
Total area 18.13mm^2
Answer:
6cm is the missing length
Step-by-step explanation:
See the 10cm and the 4cm?
If you look at in a way if you added 6 more centimeters to the 4cm it would be 10, leaving 6cm as the missing length.
You have some unknown integer

, and you know that adding this and the next two integers,

and

, gives a total of 57.
This means

The task is to find all three unknown integers. Notice that if you know the value of

, then you pretty much know the value of the other three integers.
To find

, solve the equation above:

So if 18 is the first integer, then others must be 19 and 20.
Check the picture below
area of a triangle is 1/2 bh