f(x)=3x+8 ; Find x if f(x)=12

i am in sixth grade and i need help with homework.Okaay say they give you a figure and want you to find out how many hundreths tenths and one are in the figure.how do i do that?

Each digit is the value of the respective power of ten.

Numbers get bigger to the left of the decimal point, and smaller to the right.

6 means that there are 6 ones.

46 means 4x10 + 6 so there are 4 tens and 6 ones.

3.6 = 3 ones and 6 tenths

26.198 =
2 tens
6 ones
1 tenth
9 hundredths
8 thousandths
...

To find the value of x when f(x) is equal to 12, we can set up the equation f(x) = 12 and solve for x.

Given that f(x) = 3x + 8, we can substitute 12 for f(x) in the equation:

3x + 8 = 12

To solve for x, we can start by isolating the x term. To do this, we subtract 8 from both sides of the equation:

3x + 8 - 8 = 12 - 8
3x = 4

Next, we divide both sides of the equation by 3 to solve for x:

3x/3 = 4/3
x = 4/3

Therefore, the value of x when f(x) = 12 is x = 4/3.