How do you find the zero of #f(x)=4x-12#?

Question

6734 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-10-28T15:18:15

Solve the equation for #x#, when #f(x)=0#
Then, #x=3#.

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) = 4x - 12 = 0#

First we can add 12 on both sides of the equality:

#4x - 12 +12 = 0+12#
which becomes
#4x = 12#

We can now divide both sides of the equality by 4:
#(4x)/4 = (12)/4#
and we have
#x = 3#

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