Question

A polynomial function can be written as (x + 1)(x + 4)(x - 7). What are the x-intercepts of the graph of this function ?

Answer 1

D is the answer

x+1=0

Isolate x and you get -1

Next x+4=0

isolate x you get -4

Finally

x-7=0

isolate x and you get 7

Answer 2

The x-intercepts of this graph are -1, -4 and 7.

To find the x intercepts of a fully factored function like the one above, you simply have to set each parenthesis equal to 0 and solve for x. This will give you all of the x intercepts.

FIRST ONE

x + 1 = 0 ----> subtract 1

x = -1

SECOND ONE

x + 4 = 0 ----> subtact 4

x = -4

THIRD ONE

x - 7 = 0 ----> add 7

x = 7

Now you have all of your x intercepts.