3x + 12 - 5x = 22
-2x + 12 = 22
-2x = 10
x = -5
Write the equation out, x is going to be your unknown number.
Combine like terms.
We have to isolate x, so get rid of the 12 by subtracting it from both sides of the equation.
Divide by -2.
Answer:
2.6
Step-by-step explanation:
Answer:
<em>The input when the output is 17 is x=6.</em>
Step-by-step explanation:
<u>Functions</u>
Assume the input is called x and the output is the function f(x). Two times the input is 2x. 5 more than that is 2x+5.
Knowing the output of the function is 5 more than 2 times the input, we can write the function as:
f(x)=2x+5
Now find the input x when the output is 17:
17=2x+5
Swap sides of the equation:
2x+5=17
Subtract 5:
2x=17-5=12
Divide by 2:
x=12/6=6
The input when the output is 17 is x=6.