Two different things u can do
Substitution:
X-9y=12
+9y +9y
X=9y+12
-3(9y+12)+9y=36
-27y-36+9y=36
+36 +36
-18y = 72
/-18 /-18
Y = -4
Or whatever this other I’ve is called
-3x-9y=36
-1(X-9y)=(12)-1
-3x-9y=36
-x+9y=-12
-4x=24
X= -6
Answer:
Percentage decrease = 10% × 0.82
New value = 0.82 - Percentage decrease
Let me know if this helps! :)
Answer: u r supposed to solve for substitution/add/subtract and ur answer should be (-2,9)
Step-by-step explanation: