Answer:
B
Step-by-step explanation:
Replacing <em>f</em>(x) with 21, this is the equation
21=3x+9
First, subtract 9 from each side of the equation to get:
12 = 3x
Next, divide each side by 3 to get:
4 = x
So the answer is B.
Answer: 3(x+4)<-12 and x+4<4
Step-by-step explanation:
3|x+4| - 5 < 7
First set up your two equations:
x + y = 90
x = 2y - 30
Then substitute what x equals in the second equation into the first equation:
(2y -30) + y = 90
Now solve for y:
3y -30 = 90
3y = 120
y = 40
Then use y = 40 and substitute the value for y into one of your original equations and solve for x. I'll choose the first one, but either one will work.
x+ 40 = 90
x = 50
So your solution is x = 50 and y = 40
.........................
Answer: 43
Step-by-step explanation:
