Remember you can do anything to an equation as long as you do it to both sides
x+9=18-2x
add 2x to both sides
2x+x+9=18+2x-2x
3x+9=18+0
3x+9=18
minus 9 both sides
3x+9-9=18-9
3x+0=9
3x=9
divide both sides by 3
(3x)/3=9/3
(3/3)x=3
1x=3
x=3
Answer:
a = 20
Step-by-step explanation:
The mean is calculated as
mean = 
=
= 
Then
= 27 ( multiply both sides by 5 to clear the fraction )
115 + a = 135 ( subtract 115 from both sides )
a = 20
15 + 45
GCF = 15
15/15 = 1
45/15 = 3
(15 * 1) + (15 * 3) =
15(1 + 3) <===
Answer:
1. 144 2. 16 3. 1 4. 3x-6
Step-by-step explanation:
So think of this as a function in a function. So you work from the inside to the outside. So for problem 1, we start with f(4)) [you read it "f of 4"] so what is the solution when x = 4, since f(x) means the function of x so f(4) means 'the function of 4' inside f(x).
Since f(x) = 3x then f(4) = 3(4) [notice how you substitute the 4 everywhere you see a letter x]
so f(4) = 12, now you work the next part h(f(4)) since f(4)=12 then h(12)
So take the h(x) function which is h(x) =
then h(12) =
so h(12) = 144