Answer:
(C)Determine the principal square root of both sides of the equation.
Step-by-step explanation:
Given: Isosceles right triangle XYZ (45°–45°–90° triangle)
To Prove: In a 45°–45°–90° triangle, the hypotenuse is
times the length of each leg.
Proof:

Because triangle XYZ is a right triangle, the side lengths must satisfy the Pythagorean theorem, 
Since a=b in an isosceles triangle:

Therefore, the next step is to Determine the principal square root of both sides of the equation.
Answer:
P(working product) = .99*.99*.96*.96 = .0.903
Step-by-step explanation:
For the product to work, all four probabilities must come to pass, so that
P(Part-1)*P(Part-2)*P(Part-3)*P(Part-4)
where
P(Part-1) = 0.96
P(Part-2) = 0.96
P(Part-3) = 0.99
P(Part-4) = 0.99
As all parts are independent, so the formula is P(A∩B) = P(A)*P(B)
P (Working Product) = P(Part-1)*P(Part-2)*P(Part-3)*P(Part-4)
P (Working Product) = 0.96*0.96*0.96*0.99*0.99
P(Working Product) = 0.903
You're looking for the extreme values of
subject to the constraint
.
The target function has partial derivatives (set equal to 0)


so there is only one critical point at
. But this point does not fall in the region
. There are no extreme values in the region of interest, so we check the boundary.
Parameterize the boundary of
by


with
. Then
can be considered a function of
alone:



has critical points where
:



but
for all
, so this case yields nothing important.
At these critical points, we have temperatures of


so the plate is hottest at (1, 0) with a temperature of 14 (degrees?) and coldest at (-1, 0) with a temp of -12.