Ok so first we find the equation that equals one variable.
2y = -x + 9
3x - 6y = -15
We solve for y.
2y = -x + 9
y = -x/2 + 9/2
Then we plug in this y value into the other equation to keep only one variable so we can solve for it.
3x - 6y = -15
3(-x + 9/2) - 6y = -15
-3x + 27/2 - 6y = -15
-9y + 27/2 = -15
-9y = 3/2
-y = 3/18
y = -3/18
Then we plug in this numerical y-value into the first equation which we found out by solving an equation for y.
y = -x/2 + 9/2
-3/18 = -x/2 + 9/2
-84/18 = -x/2
-x = 9 1/3
x = -28/3
Your answer would be (-28/3, -3/18)
Hope this helps!
Step-by-step explanation:

its hard to determine without the known value of x, but the above would be the equation needed to solve it if you knew what x was
Answer:
There is a 30% decrese.
Step-by-step explanation:
Answer:
1. 5x+3y, 2. 5h, 3. 5x+20-2x+8 --> 3x+28, 4. 2y-6+5x+5 --> 2y+5x-1
Step-by-step explanation: