Topic 3 Similar Figures (U1)

Question 1

What is the formula to calculate the scale factor (k)?

Answer 1

k= L/l

Question 2

What is the formula to calculate the image length (L)?

Answer 2

L=kl

k x l

Question 3

What is the formula to calculate the original length (l)?

Answer 3

l= L/ k

Question 4

What are the tests to find similar triangles?

Answer 4

• AAA (angle - angle - angle)
• SSS (side - side - side)
• SAS (side - angle - side)
• RHS (right angle - hypotenuse - side)

Question 5

A scale of 1: 100 means that every?
1mm on plan = __ in actual measurement.
1cm on plan = __ in actual measurement.
1m on plan = __ in actual measurement.

Answer 5

1mm on plan = 100mm in actual measurement.
1cm on plan = 100cm in actual measurement.
1m on plan = 100m in actual measurement.

Question 6

The scale can be expressed as a fraction, what does this look like?
1: 100 =

Answer 6

1/ 100

Question 7

A scale of 100: 1 means that every?
100mm on plan = __ in actual measurement.
100cm on plan = __ in actual measurement.

Answer 7

100mm on plan = 1mm in actual measurement.

100cm on plan = 1cm in actual measurement.

Question 8

What is the formula to calculate the missing area?

Answer 8

k2= A/ a

2 is squared

Question 9

What is the formula to calculate the volume of the image?

Answer 9

V= k3v

3 is squared
(k3 x v)

Question 10

What is the formula to calculate the volume of the original?

Answer 10

v= V/ k3

3 is squared

Question 11

What is the formula to calculate the scale factor in volume?

Answer 11

k3= V/ v

3 is squared