Answer:
its 42
Step-by-step explanation:
315-18+81=378
Correct mean =378/9=42
Answer:
it could be a formula ex- l times w = area
Step-by-step explanation:
3x + 4y = 38 ( equation 1) ----> ×5
5x - 5y = -30 ( equation 2) ----> ×3
When you multiply eqn 1 by 5 you get, 15x + 20y = 190
And when you multiply eqn 2 by 3, you get, 15x - 15y = -90
Then you solve both equations by subtracting eqn 2 from eqn 1
15x + 20y = 190
15x - 15y = 90
Then 15x - 15x gets cancelled and 20y - (-15y) gives 35y and 190 - (-90) gives 280.
So that gives 35y = 280
y = 8
And when you replace y = 8 in any of the two equations, x = 2
The answer would be: x+2y
First, combine the like terms.
-x and 2x
Now your equation looks like this:
x+y+y
Now combine the y like terms.
y and y and you get 2y
Then you are left with your answer: x+2y
Hope this helps! :3