Question

Find the zero of the function below:
f(x) = 4x + 12

Answer 1

Solve the equation for
x
, when
f
(
x
)
=
0

Then,
x
=
3
.
Step-by-step explanation:
I assume you mean to find the solution/root (radical)
x
, when
f
(
x
)
=
0
.
Then, this is simple.
Just set
f
(
x
)
to 0 and solve the equation for
x
:
f
(
x
)
=
4
x
−
12
=
0
First we can add 12 on both sides of the equality:
4
x
−
12
+
12
=
0
+
12

which becomes
4
x
=
12
We can now divide both sides of the equality by 4:
4
x
4
=
12
4

and we have
x
=
3
The "zero", or the solution for
f
(
x
)
=
0
is
x
=
3
.
Q.E.D.

Answer 2

x = - 3

Step-by-step explanation:

To find the zero, let f(x) = 0, that is

4x + 12 = 0 ( subtract 12 from both sides )

4x = - 12 ( divide both sides by 4 )

x = - 3 ← is the zero