# Solving Equations

In this chapter we will look at ways in which you can solve equations.
You need to identify what type of equation so that you can decide which method to use.

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Slide 1: Slide
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This lesson contains 20 slides, with interactive quizzes and text slides.

Lesson duration is: 50 min

## Items in this lesson

In this chapter we will look at ways in which you can solve equations.
You need to identify what type of equation so that you can decide which method to use.

#### Slide 1 -Slide

How well have you understood this chapter?
We will now solve some equations to see how well you have understood the explanation. Maybe you don't know how to solve all of the types of equation and need extra explanation.

#### Slide 2 -Slide

Solve equation a)
x=?

#### Slide 3 -Open question

Solve equation b)
x=?

#### Slide 4 -Open question

Solve equation c)
x=?

#### Slide 5 -Open question

Solve equation d)
x=?

#### Slide 6 -Open question

Solve equation e)
x=?

#### Slide 7 -Open question

Solve equation f)
x=?

#### Slide 8 -Open question

All answers correct or only one mistake
You have understood the basis of the chapter .
Now you can practise questions with more text .
ex 32 t/m 38 on pages 88 & 89

#### Slide 9 -Slide

Maybe you were just unlucky so try some more and see if you do any better this time.
T7 & T8 on page 93
ex 35, 37 and 38 on page 89

#### Slide 10 -Slide

More than two mistakes
Never mind!
With a bit more explanation you will do better next time!

#### Slide 11 -Slide

Solving an equation using cards
6k+12=30
Think carefully where the card should be placed.
Work out what number should be written on the card?
What is k equal to?

#### Slide 12 -Slide

"expressed in terms of"
In the formula y=4x+7 We say y is"expressed in terms of" x
Sometimes you need to re-arrange the formula to get it expressed in this way.
eg. 6q + 12p = -18
6q = -18 -12p    and dividing by 6 gives
q = -3 -2p

#### Slide 13 -Slide

Simultaneous equations
You can solve simultaneous equations
by first re-arranging the formulas and then putting them equal to each other so that you have an equation to solve.
y=3x+7
y+4x=0    becomes  y = -4x
so 3x+7 = -4x
7x = -7  so x = -1
or
by substituting
y=x-1 and 4y+ x = 16 so gives 4(x-1)+x = 16
4x-4+x=16  which is 5x=20 so x=4

#### Slide 14 -Slide

Fractional equations
Using Cards
18/(2x+1) =2
so 2x+1 = 9 so 2x=8   x=4
However if there are variables on both sides of the equation, multiply both sides by the denominator of the fraction.
(x+7) = -9/(x-3)
(x-3)(x+7) = -9 you can now solve giving x=-6 or x=2

#### Slide 15 -Slide

Exponential equations
These are equations like:

To solve these you need to write the number also as a power

#### Slide 16 -Slide

square root equations
Square both sides to remove the square root. Or use cards.
Then you can solve in the usual way.

#### Slide 17 -Slide

power equations
These are equations that contain a power of the variable.

#### Slide 18 -Slide

Now you are ready to try again!
T1,  T2 a,b,c   , T3, T4, T5 a,b,c  , T6 a,b,c
and
ex 36  on page 89