Question

Identify the zeros of each function.

1. y = 5(x - 3)(x + 5)
2. y = (x - 9)(x + 4)
3. y = (x - 7)

Answer 1

1. The zeros are x = -5 & 3

2. The zeros are x = -4 & 9

3. Zero = x = 7

Explanation:

Whenever we have an expression in the form:

`(x-a)(x-b)`

Where a and b are constants

To find zeros, we take each term and equate to zero. That would be:

x - a = 0

x = a

and

x - b = 0

x = b

Likewise, let's find the zeros of each of the functions given:

1.

`y = 5(x - 3)(x + 5)\\0=5(x - 3)(x + 5)\\0=(x - 3)(x + 5)\\`

So,

x - 3 = 0

x = 3

and

x + 5 = 0

x = -5

The zeros are x = -5 & 3

2.

`y = (x - 9)(x + 4)\\0=(x - 9)(x + 4)`

So,

x - 9 = 0

x = 9

and

x + 4 = 0

x = -4

The zeros are x = -4 & 9

3.

`y = (x-7)\\0 = (x-7)`

x - 7 = 0

x = 7

The zero of this function is x = 7