I used the Old Change New method and I crossed multiplied.
The answer is about $498 (I rounded $497.895875)
Check: $498>459.95 by 8.25%
The answer would be d. Because the identity property of addition is that if you add zero to any number the number stays the same
25 Planes can take off. Divide 60 (minutes) by 12 and it should give you 5. Take that five and multiply it by the number of hours they are asking for (5). 5*5=25.
It is true due to the commutative property of multiplication. If all of your operations are multiplication, then the integers can move around and you can still get the same answer.
^This is only true if you meant to type (1.8x3)x2.1=(1.8x2.1)x3
If you meant what you typed, then the equation is false. The left side would be 3 times the value of the right side due to the 3 being on the left side and not the right side while without the 3 the two sides would be equal.
X is the radius of the slice. So we must find the equation of the side of the cone.
y=mx+b, so now we must use two points to solve for the slope, or "m".
m=(y2-y1)/(x2-x1)
m=(0-15)/(5-0)
m=-15/5
m=-3 so our line so far is:
y=-3x+b, b=y-intercept=value of y when x=0, which we can see is 15 ft so:
y=-3x+15
Now the radius is x, so we must solve for x from the equation above...
-3x+15=y subtract 15 from both sides
-3x=y-15 divide both sides by -3
x=(15-y)/3
And area of this circle is:
A=πx^2, and using x found above:
A=(π/9)(15-y)^2
A=(π/9)(225-30y+y^2), so when y=6 ft
A=(π/9)(225-30*6+6^2)
A=(π/9)(81)
A=9π or if we let π=pi
A=9pi ft^2