Notes: Algebra

1) Isolate the variable (get it by itself).

2) What you do to one side of the expression, you must do to the other.

for example:

After you get your answer, check it, using this technique:

1) Copy the equation again (A+4=10)

2) Just replace every "a'' you see with your answer for the equation (6)

You will end up with this:

Here are other examples:

B - 2 = 5

B - 2 + 2 = 5 + 2

B = 7

2j + 1 = 9

2j + 1 - 1 = 9 - 1

2j + 1 - 1 = 9 - 1

2

j=4

Here's a link to help you with it: I love algebra.

And a link to the video.

Answer to Camille's Question

Question: There's 6 pencil crayons in a box. It has 1 blue, 1 green, 1 yellow, 1 red, 1 orange, and 1 pink. what is the probability of him getting a yellow pencil crayon?

Answer: There are 6 pencil crayons, and 1 yellow pencil crayon.

Probability Question

It's Annie's birthday, and there are 9 people attending the party.

There are 8 balloons: a red, blue, green, purple, black, white, yellow, and brown-ish one.

What is the probability of a person not getting a balloon? Express the answer as a ratio, fraction, and percent.

Here's a link that will help you answer the question.

Also a video...

Questions 10-12

10) A parallelogram-shaped stripe is going to be painted on the wall of a daycare center. There is enough paint to make a stripe with an area of 9m². How high can the stripe be?

The answer is 6m²

All you have to do is divide 9 by 1.5

9 ÷ 1.5 = 6

11a) With a ruler, measure the base and height of the parallelogram. Explain how you measured.

The parallelogram looks something like this:

First, measure any of the 4 sides and remember that it is your base (b). Then, measure the line perpendicular to it, and that is your height (h). In this case, the base is the vertical left side, and the height is the top horizontal side.

11b) What is the area?

b = 2cm h=1.5cm

2cm × 1.5cm = 3cm²

11c) Use a different side of the parallelogram as the base. Determine the new height and calculate the area.

Use the vertical right side as your base, and use the bottom horizontal side as your height.

b= 2cm h= 1.5cm

2cm × 1.5cm = 3cm²

How does this compare to your answer b)?

They are both the same answers, because the sides of 11b) are equal to the sides of 11c), making the opposing sides parallel (bottom and top horizontal lines parallel, left and right vertical lines parallel).

12) Which of the 2 shapes shown below has a greater area? Explain your answer.

The picture looks like this:

Both of these shapes have an equal area, because their length and base are the same distance apart, and they are both perpendicular.

Here is also a link to help you with the Area of a Parallelogram

And a video to help too.

Math Questions 1-3

1. Annie was asked to calculate 1.7 + 6÷2. She claims the answer is 3.85.
Do you agree?
Explain why or why not.

No, I do not agree with Annie because the first thing you had to do was divide 6 by 2, so the answer is 3.

1.7 + 3 = 4.7

Annie got the answer 3.85 by adding 1.7 to 6 to get 7.7, then divided 7.7 by 2 to get the answer 3.85.


2. Put brackets in the following expression to get the largest value possible.
What problem solving strategy did you use?

3 × 2.8 + 6.4 ÷ 4 = ?

(3 × 2.8) + (6.4 ÷ 4) = 10


3. Create a problem that could be solved using the following expression.

2.5 + 1.25 + 5 × 1.6 = 14

Emma was shopping for school supplies, and bought a calculator for $2.50. Then she bought a box of pens for $1.25, and 10 pencils for $5. Without the taxes, Emma would have to pay $8.75, but with the taxes, she would have to pay $14 for the school supplies.

B.E.D.M.A.S

B- Brackets ( )

E- Exponents a²
D- Division ÷
M- Multiplication ×
A- Addition +
S- Subtraction -


For Example:

If you are still confused about B.E.D.M.A.S, here is a video that will help:



Here is also a link to help you.

Corrections for #8

8. In which quadrant is the point with coordinates (3,8)?
Answer: A (Quadrant I)
If can't tell the quadrants apart, like me, the bottom left quadrant is quadrant III
The top left quadrant is quadrant II
The bottom right quadrant is quadrant IV
And the top right quadrant is quadrant I

Remember that the x-axis always comes first, so you move the point 3 units across the x-axis, and 8 units up.


Sorry I couldn't put up any videos or pictures, but I hope I help you as much as I could!