Step-by-step explanation:
x^2 + 10x = -25
x^2 + 10x + 25 = 0
（x+5)^2=0
x=－5
Multiply equation II by 2 and then add up the equations.
1,3,5
4 looks like true but decreasing but 2 dollars also gives max revenue, so I not sure about it
Answer: $11.80 for another 4 panes of glass.
Step-by-step explanation: We know that 9 panes of glass cost $26.55, but we should first find how many dollars would it cost per pane of glass, or 1.
So, we can divide 26.55 by 9 to find the price per 1 pan of glass.
26.55/9 = 2.95, or $2.95 per pane of glass.
Now, we want to know how much it will cost for 4 panes of glass. Simply multiply 2.95 by 4.
2.95 x 4 = 11.8, or $11.80 for another 4 panes of glass.
