1819 H2Y §5.Refresh

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• Leerjaar 2

What are these graphs called?

CH5 Quadratic Formulas

Quadratic formulas are the type of formulas you will use most often in Mathematics.

Working with quadratic formulas requires you to work precisely and neatly and you need the skills you've learned in previous chapters.

Recap: Order of Operations

When doing calculations, you have to follow the order of operations:

1. First calculate what is given between brackets.

2. Then calculate powers and roots.

3. Then multiply and divide from left to right.

4. Then add and subtract from left to right.

           

Recap: Square roots

The square root of 25 is 5, because the square of 5 is 25.

The square root of 6.25 is 2.5, because the square of 2.5 is 6.25

There is no square root of -16 (or any other negative number), because there is no number you can square to get a negative result

Recap: Writing formulas shorter

You can write formulas shorter by:

- multiplying factors

- combining like terms

- not writing down the multiplication sign between a number and a variable

Recap: Quadratic formulas

If a formula contains a the square of a variable (and not a higher exponent), it is called a quadratic formula.

The corresponding graph is called a parabola.

When filling in negative numbers for the variable in a quadratic formula you should use brackets, because you want to square the negative number, not take the opposite of a positive square.

Pen&Paper or Digital

For this chapter you will get to choose between doing most of your exercises on your iPad or in your notebook.

- If you work in your notebook, you can follow the studyplanner for your chosen path (support, standard or challenge). Check your answers with the solutions book, if you get an answer wrong, try answering the question again.

- If you work on the iPad, I will keep track of the time you spend on your exercises and how well you did on them.  Some exercises (such as drawing graphs) you will have to write in your notebook. Your answers will be checked for you. If you get an answer wrong, try answering the question again.

HW Monday

Make and correct §5.Refresh

(digital or from your book)