Combination of topics 

Questions that combine topics and often have a quadratic twist

1

The diagram shows a rectangle garden with lengths as shown.

a Show that the area, A(x) is given by the formula A(x) = x² + 9x + 20

1 Marks

b The area of the garden is 56m².

Determine the value of  x.

4 Marks

Show Answer

x= 3

2

A right angled triangle has dimensions as shown

Calculate the length of KH.

Give your answer as a surd in its simplest form

3 Marks

Show Answer

4 root 3 m

3

A vegetable garden consists of a greens patch in the centre and a path around the edge.

The path is x m wide.

The length and breadth of the entire garden are 13m and 11m respectively.

The area of the greens patch is 82m²

a Write an expression in terms of x for the length of the greens area.

1 Mark

b Hence, show that 4x² - 48x + 61 = 0

2 Marks

c Calculate x, the width of the path.

Give your answer correct to 1 decimal place

4 Marks

Show Answer

a 13 - 2x

c 1.4m

4

The diagram shows a plan of a garden.

The grass section is in shape of a rectangle and a the paved section is in the shape of a right angled triangle.

The total area of the garden is 24m².

a Write the length of the paved section in terms of x.

1 Marks

b Hence, show that x² + 10x - 24 = 0

2 Marks

c Determine algebraically, the value of x.

3 Marks

Show Answer

x = 2m

5

Solve the equation x² – 6x – 3 = 0

Give your answer in the form: 

4 Marks

Show Answer

3 plusminus 2 root 3

6

In triangle ABC


The area of triangle ABC is 60cm²

a Show that x² + 7x - 60 = 0

2 Marks

b Hence, algebraically determine the value of x.

3 Marks

Show Answer

5cm

7

A right angled triangle is shown below.

It has sides of x cm and 12cm

The hypotenuse if 2x cm

Calculate the value of x

Give your answer as a surd in its simplest form

3 Marks

Show Answer

4r3

8

The two triangles shown are mathematically similar

a Show that x² + 7x - 60 =0

2 Marks

b Hence, determine the value of x

2 Marks

Show Answer

5

9

A rectangular garden has an area of grass and an area of pavement as shown.

The area of grass has length 7m and breadth 5m.

The path around 2 edges of grass has width x m

a Write down an expression for the length of the garden in terms of x

1 Marks

b Hence show that the area of the whole garden is given by A(x) = x² + 12x + 35

2 Marks

The area of the garden is 90m²

b Determine the value of x

3 Marks

Show Answer

a x + 7

c 3m

10

Triangle RST is shown.

Cos R = 0.5

Calculate the side ST.

Give your answer as a surd in its simplest form

3 Marks

Show Answer

3 root 3

11

A force is represented by the vector u

The magnitude |u| of the vector is 

a Show that x² + 2x - 15 = 0

3 Marks

b Hence, determine the possible values of x

2 Marks

Show Answer

x = -5 or 3

12

The floor plan of a ball room consists of a rectangle and a segment of a circle as shown,

a Calculate the length of line OK

3 Marks

b A border is to be fitted around the perimeter of the room.

Calculate the length of border required.

4 Marks

Show Answer

b 30.7m