Hello!
To find the greatest common factor, you must find all the factors of both numbers and see which similar one is the greatest.
27: (1,27) (3,9)
36: (1,36) (2,18) (3,12) (4,9) (6,6)
As you can see the, the greatest common factor is 9.
I hope this helps!
Answers:
So the solution is (x,y) = (4, -1)
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Work Shown:
6x + 7y = 17
6x + 7( y ) = 17
6x + 7( -3x+11 ) = 17 ... replace every copy of y with -3x+11
6x - 21x + 77 = 17
-15x = 17-77
-15x = -60
x = -60/(-15)
x = 4
We'll use this x value to find y
y = -3x+11
y = -3(4)+11 ... replace x with 4
y = -12+11
y = -1
We have x = 4 and y = -1 pair up together to give us the solution (x,y) = (4, -1)
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To check the solution, we plug x = 4 and y = -1 into each equation
Plugging the values into the first equation leads to...
y = -3x+11
-1 = -3(4)+11
-1 = -1
This is effectively already done in the last part of the previous section. But it doesn't hurt to verify like this regardless.
We'll need to verify the second equation as well.
6x + 7y = 17
6(4) + 7(-1) = 17
24 - 7 = 17
17 = 17
We get a true equation, so the solution is confirmed with both equations. Overall, the solution to the system of equations is confirmed. This system is independent and consistent.
You combine both 2x-12 and x+2 and 11 which makes the equation
2x-12+x+2= 11
The you get your answer which is
X=7