I suggest reading them over and over again to remember them. I know it sounds annoying, but trust me, it'll pay off.
Answer:
168 in²
Step-by-step explanation:
The square would be 36 in²
Area of a triangle is A= 1/2 bh
A = 1/2 (11 x 6), A= 1/2 (66)
1/2 (66) = 33 in², which is the area of a triangle.
Then you multiply 33 x 4 to get the area of all the triangles, which is 132 in²
You add the area of the square to the area of the triangles, which is 168 in².
Start with

Add 2x to both sides:

Subtract 21 from both sides:

Divide both sides by 5. Since it is positive, we don't have to change the inequality sign:

So, the answer is 
<span>The place value positions to either side of a number are related because they are 10 times smaller or ten times bigger — a number in the hundreds column in ten times bigger than the same number in the tens column, for example.</span>