-3x + y - 2z = 10 |* -1
3x - y +2z = -10
5x -2y -2z = 12
--------------------------- I add these equations term by term
8x - 3y = 2
-3x + y - 2z =10 ⇒ -3x + y - 2z =10
x -y +z = 23 | *2 2x - 2y + 2z = 46
----------------------------- I add these eq.
-x -y = 56
8x - 3y = 2
-x -y = 56
this is the system after i reduce it ( it has only two variables x and y)
Answer:
120*2.75*60/5280
= 3.75
Step-by-step explanation:
So James is walking at 120 steps a minute, there are 60 minutes in one hour, and 5,280 feet in a mile. So, to find how quickly James is walking, we multiply how many steps he is taking a minute by how much distance each step is (120 * 2.75) that gives us how much distance in one minute, so we then multiply by 60 because there are 60 minutes in one hour. Then divide the entire equation by how many feet are in one mile (5,280) giving us the answer 3.75 miles per hour. And the equation 120*2.75*60/5280
10 inches x 8 inches.
You can get this by creating two equations.
xy = 80 and 2x + 2y = 36
Then you can solve the first one for either variable. Once you do that you can substitute it into the other equation and solve. You'll get a quadratic equation which will give you both parts of the answer.
<span>P(x)=-5x^2+300x+15,000 is the equation of a parabola and represents profit. Its graph opens down. Our job is to find the x-coordinate of the vertex (which is the x-coord of the maximum profit) and then the corresponding y-value.
The formula x = -b / (2a) will produce that x-coordinate:
-(300)
x = ------------ = 30
2(-5)
When x=30 units, y = profit = -5(30)^2 + 300(30) + 15000 = $19500 (answer)
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