Answer:
81-25k²
Step-by-step explanation:
We need to write the expression for "The quantity 81 minus 5k, squared".
Square of any number x is given by x².
Square of 5k is given by : (5k)²= 5²×k²=25k²
Now subtract 25k² from 81.
It means we get : 81-25k². It is required expression.
In order to get the area of a triangle using sides, the formula that we are going to use is Heron's formula. This is after from "Hero of Alexandria".
So here is the step by step process:
First, we calculate for s (half of the triangles perimeter) s = a+b+c divided by 2.
s = 6 + 10 + 12 / 2
s =28/2
s = 14
Now that we have the s, we can now calculate for the area.
A = square root of s(s-a)(s-b)(s-c)
A= square root of 14 x 8 x 4 x 2
A= square root of 896
A = 29.93
The area of triangle DEF is 29.93 square feet or 30 square feet. Hope this answer helps.
the standard form for a horizontal ellipse is
X^2/a^2 + y^2/b^2 = 1
Substitute 54 for b and and use (8,18) as the
point to find a
x=8
y=18
8^2/a^2 + 18^2/54^2 =1
64/a^2 + 324/2916 = 1
324/2916 reduces to 1/9
64/a^2 + 1/9 = 1
64/a^2= 1-1/9
64/a^2 = 8/9
64*9/8 = a^2
576/8 = 72
A^2 = 72
A = square root(72) = 8.485
So formula
would be x^2/72 + y^2/2916 =1
Answer:
(3,1)
Step-by-step explanation:
16.5 degrees below the starting temp, whatever that is. If its 0, then -16.5 degrees.
The first equation would be (.5)5-11=-8.5, because the metal has been cooling for 5 hours.
The device that 'aids' in the cooling would be -5-3=-8, because it is a separate variable that cools the metal, so the amount the device cools is independent of the natural cooling amount, and the equation is independent of the natural cooling equation.
You then add -8.5 and -8, because the device has lowered 8.5 degrees and 8 degrees. This equals -16.5 degrees, or a decrease of 16.5 degrees.