Cagri T. answered 7d
5+ years private tutoring to elementary and middle school students.
Without making a few assumptions, it is not possible to solve this question as it is not very clear (and the figure is not drawn to scale using the squares)
My assumptions are:
1 - The triangle is an equilateral triangle with a side length A = 6.
2 - The 4-sided shape in the middle is a rectangle with width (W) = 6
3 - The curve at the bottom is a semi-circle and 10 corresponds to the diameter (D) of that circle.
4 - The diameter of the semi-circle is exactly half of the longest side of the rectangle.
With the above assumptions, you can move forward as follows:
1 - Long side of the rectangle (L) is 20 since it is equal to 2 x 10
2 - The remaining length of L excluding the base of the triangle (K) is 20 - 6 = 14
3 - The length of the half circle (H) = 1/2 x D x (pi) where pi=3.14. So H = 1/2 x 10 x 3.14 = 15.7
The perimeter of the irregular shape (P) is calculated as follows:
P = (2 x W) + (L - D) + H + K + (2 x A)
By plugging the numbers in, we get:
P = (2 x 6) + (20 - 10) + 15.7 + 14 + (2 x 6) = 63.7