## Lesson details

### Key learning points

1. In this lesson, we will learn how we can factorise quadratics using an array.

### Licence

This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

## Video

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## Worksheet

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## Starter quiz

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### 6 Questions

Q1.
Which expression is equivalent to a² - b² ?
(a - b)(a - b)
Correct answer: (a + b)(a - b)
2ab
ab
Q2.
Match the expression equivalent to (x+4)(x-4).
x² - 16x
x² - 4
x² - 8x + 16
x² + 4²
Q3.
Match the expression equivalent to (x+9)(x-3).
Correct answer: None of the above.
x² - 3²
x² - 6²
x² + 3x - 27
Q4.
Which calculation would work out 64² - 4² ?
(8 x 2)²
60 x 60
72 x 6
Q5.
Match the expression equivalent to (x+25)-(x-25).
x² - 25
x² - 25²
x² + 5²
Q6.
Match the expression equivalent to (73+x)(73-x).
73 - x²
73 + x²
x² - 73
x² - 73²

## Exit quiz

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### 6 Questions

Q1.
Fill in the gap: ________ is the opposite of expanding.
Increasing
Solving
Q2.
Factorise x² + 11x + 24.
(x+2)(x+12)
(x+5)(x+6)
(x+6)(x+4)
Q3.
Factorise x² + 14x + 24.
(x+3)(x+8)
(x+5)(x+6)
(x+6)(x+4)
Q4.
Factorise x² + 8x + 16.
(x+16)(x+1)
(x+4)(x+2)
(x+8)(x+2)
Q5.
Factorise x² - 25.
(x-5)
(x-5)²
(x+5)²
Option 5
Q6.
A quadratic expression x² + bx + 20 can be factorised. Find all the possible values for b when b is positive.
1 to 20
1, 20, 2, 10, 5, 4
15, 5