## Gathering Information

## Angles

It seems like ages ago, but we worked with blocks to show lots of things about angles before schools were closed. Here are my pictures, for use in our learning portfolios.

We also learned that the interior angles of a triangle add up to 180 degrees, and the interior angles of a quadrilateral add up to 360 degrees. Both of these can be proven by creating a triangle (or quadrilateral, as shown), labelling and identifying the angles, and the ripping the shapes up to separate the angles.

The angles then ca be reassembled together, and in this case we see that they go all the way around a circle or 360 degrees. In the case of a triangle, they all come together to make a straight line, or 180 degrees.

We next had a look at desmos geometry, and we investigated how joining the midpoints of any quadrilateral will create a parallelogram in the middle.

We can prove it’s a parallelogram by measuring angles. Opposite angles are congruent. Also parallel sides will be the same length. With desmos geometry we can drag and drop any of the corners to shift the shape, and see that the resulting interior quadrilateral is always a parallelogram!

## Which one is bigger?

In 1L we are now looking at triangles, and other shapes. We wondered which was bigger, the rectangle or the triangle….

or which was bigger, the rectangle or the parallelogram….

We had a good discussion, and compared the two. Each of the shapes has the same area, as they were made by cutting the rectangle along the diagonal, and then rearranging the pieces. The perimeter is not the same for the shapes though!

We determined that the area of a triangle is half of the area of the rectangle that it came from.

## First math test

First grade 9 math test today! We prepared well, and are ready to show what we can do. We know that the first test is often a learning experience!

## Working on Perimeter and Area

We’re working on calculating perimeter and area in our 1L math class now.

Today we modelled a rectangle on the floor, and made use of the tiles to help us determine the perimeter and area.

We know that to determine the perimeter, we add up all the sides, or we can add the length and width and then double the result, or we can double the side lengths and then add the results.

To determine the area we we are working on multiplying. We know we can count the squares, or we can multiply length by width by skip counting, or by making groups.

We followed up with another area game!

## Test Review

We’ve got last minute test preparations happening today. We worked in pairs at the boards, and solved questions at stations around the room.

We are now able to do many skills. We can calculate the surface area and volume of spheres, cones and square based pyramids, we can optimize the surface area and volume of rectangular prisms, we can calculate the perimeter and area of composite shapes, and we can represent exponents in 3D models (using toothpicks and skewers and clay).

We’re ready for tomorrow’s test!

## Area of rectangles

We played a game in 1L today to help us practice the area of rectangles.We played in pairs. Each person took a turn to roll 2 dice, and then colour in a rectangle with the dimensions of the numbers on the dice. Each person needed to then state the area of their rectangle. There was some strategy about where to place the rectangles, to mess up the future plans of your opponent.

In the end, to determine who won, we needed to determine who had the most area coloured in. We divided up the regions into smaller rectangles and calculated those areas and added them up.