Always, sometimes or never? | Assessment Resource Banks

This task requires you to know if equations are always true, only true for some values of x, or never true.

Some equations are always true.

e.g., 2x = x + x is true for all values of x (3, 5.5 etc)

Some equations are only true for some value of x.

e.g., x + 1 = 2 is only true for one value of x (i.e., x = 1)

Some equations are never true.

e.g., x = x + 1 is never true whatever value x takes.

Question

a) Select the correct option for this equation: 2x = 8

- It is never true.
- It is true for only one value of x.
- It is true for only two values of x.
- It is true for any value of x.

Explain your answer.

b) Select the correct option for this equation: (x + 1)(x – 2) = 0

- It is never true.
- It is true for only one value of x.
- It is true for only two values of x.
- It is true for any value of x.

Explain your answer.

c) Select the correct option for this equation: 4 (x + 3) = 4x+ 7

- It is never true.
- It is true for only one value of x.
- It is true for only two values of x.
- It is true for any value of x.

Explain your answer.

d) Select the correct option for this equation: x² = 16

- It is never true.
- It is true for only one value of x.
- It is true for only two values of x.
- It is true for any value of x.

Explain your answer.