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5
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because i need to understand not just the answer

 Jun 17, 2020
 #1
avatar+986 
+1

A composite figure is broken up into smaller pieces that are easy to solve.

 

There are two ways to break up into rectangles. 

 

Either vertically or horizonatally(for this one)

 

If we do vertical, we have 2 rectangles that are size of 3*5 and 2*4.

 

3*5 + 2*4 = 15 + 8 = 23.

 

If we split it the other way, 

 

3*3 and 2*7.

 

9 + 14 = 23.

 Jun 17, 2020
 #2
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+1

I had another answer but im not pretty sure


 

 

Since the squares are each 1 cm × 1 cm, you can technically count all the shaded squares, but it is good to do it mathematically.

We can separate this shape into 1 parts. The top part sticking up is a square and the bottom, a rectangle. We find the area for both parts and add them together.

Square:

3 cm × 3 cm = 9 cm²

Rectangle:

2 cm × 7 cm = 14 cm²

Total:

9 cm² + 14 cm² = 23 cm²

 Jun 17, 2020
 #3
avatar+986 
+1

yeah, that's the other way as I wrote for "horizontally"

 

Do you need any clarification/ further explantion?

 

Also, many times, you don't have a grid, so learning to solve algebraicly is better than counting.

hugomimihu  Jun 17, 2020
edited by hugomimihu  Jun 17, 2020
 #4
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0

no thanks im good :)

 Jun 17, 2020
 #5
avatar+986 
+2

alright great!

hugomimihu  Jun 17, 2020

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