Well, variables are stuff like x and y because they can represent a number. They are variable in an equation. so if you have (3x^3)+(5X^2)+Y+9 then your variables are x X and Y (im assuming the capital X is there and not a typo) if that was a typo and meant to be lowercase, then its just a 2 variable with the x and y
Answer:
492.99
Step-by-step explanation: x = amount invested at 12%
y = amount invested at 9%
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x + y = 20287
0.12x = 0.09y + 492.99
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put the system of linear equations into standard form
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x + y = 20287
0.12x - 0.09y = 492.99
Answer:
s=7
p=3s
Step-by-step explanation:
The perimeter is the side length times 3
So the equation would be p=3s
Plug in 21 for p
21=3s
That means s=7
Circumference is a linear distance. So if the diameter is in feet, then the circumference is also in feet (not square feet or cubic feet)
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Example:
Let's say we had a circle with diameter d = 10 feet
The circumference is approximately...
C = pi*d
C = 3.14*10
C = 31.4
The circumference is roughly 31.4 feet
The circumference is essentially the distance around the circle's edge. We can use a flexible ruler or a string to help measure out this distance, or you can imagine laying the circle's edge to be placed along a straight line, which is another way to help measure the perimeter.