Finding the Area of A Triangle

To find the area of a triangle, you can use two ways. The first way, is to find the area of a parallelogram or a rectangle, and cut it in half. Pretend the area of a rectangle is 36. Since you cut the rectangle in half, you cut the area in half. So, 36 divided by two equals eighteen. The area of this triangle is 18 cm2.

The second way is to measure the triangle from the top corner down to the base of the triangle. Multiply the base by the height of the triangle. Then you will have the area of the triangle.

Finding The Area of a Parallelogram

To find the area of a parrellogram, measure the width (or the base) and the length (or the height). Then, multiply the width by the length. Pretend that the parallelogram has a 3 cm base, and a 4 cm height. Multiply three cm, by four cm.

3cmX4cm=12cm.

So, the area is 12cm.
Another way is to measure the parrelellogram on graph paper. If it's on graph paper, count all the full squares in the parallelogram and write it down, then, using your imagination, put the unful squares together, and count them as a full square. If you use these strategies, you'll figure out the area of a parelleogram in no time flat.

The Perimeter of a Triangle

The missing measurment for the triangle's perimeter is 6.9 cm. Here is how I figured it out:


5cm
+41mm
-------
9.1 cm

I know that 10 mm make 1 cm, so, 41 mm is 4.1 cm. + 5 cm = 9.1cm. Which means, to get to 16 centimeters, you have to add 6.9 cm to find the perimeter of the triangle...

9.1 cm
+ 6.9 cm
-----
1 6 cm

Now, that's 16 cm. So, in mm, it's 160mm. basically, instead of adding 5 + 4.1, you'd add
50 mm + 41mm.
And, instead of adding 9.1 + 6.9, you'd add 91mm + 69mm.
So, that's basically the perimeter of the triangle. 16 cm and 160 mm.

The Method I Prefer

I think the method I prefer is Dimenico's method, because his method is simple, it doesn't loom comfusing, and it's especially simple if you think about it. It's really easy to see where he's coming from.

Finding the Perimeter of Polygons

I have learned that you don't have to use a ruler or a meter stick to find the perimeter. You can add or multiply to get the perimeter. For example: 2 sides of a square are 3cm, and 2 sides are 4 cm, then you add the 4 sides together, and you get the perimeter of the square. But, usually, you have to mesure the polygon to find the area.

Patterining Reflection

I thought the patterning unit was easy. There were some hard assignments, but the unit was mostly really easy. The only thing was that we got three sheets for homework when we got homework. That was the hardest part.
I learned that some patterns just have the same thing about themselves through the whole pattern, and not all patterns have to have like, a square a circle, then a square again.

Welcome!

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