Answer:
Step-by-step explanation:
Answer:
8x + 108 = 9
Step-by-step explanation:
Given
x + 9 = 
Multiply through by the lowest common multiple of 3 and 4, that is 12 to clear the fractions.
8x + 108 = 9 ← equivalent equation with no fractions
The original side length was 12m therefore the perimeter was 36m. 12/4 is 3 so the perimeter is now 9, and the difference between them is 27.
Answer:
Step-by-step explanation:
x-y=7
-3x+9y=-39
Divide the second equation by 3
-x +3y = -13
Add this to the first equation
x-y=7
-x +3y = -13
----------------------
0x +2y = -6
Divide by 2
2y/2 = -6/2
y = -3
Now find x
x-y = 7
x -(-3) = 7
x+3 = 7
Subtract 3 from each side
x = 4
(4,-3)
Or by substitution
x-y=7
solve for x
x = 7+y
-3x+9y=-39
Substitute y+7 in for x
-3(7+y) +9y = -39
Distribute
-21 -3y +9y = -39
Combine like terms
-21 +6y = -39
Add 21 to each side
6y = -18
