12 is 9.52380952381% of 126
Answer:
Part 1) 
Part 2) 
Step-by-step explanation:
Part 1)
we know that
The perimeter of triangle is equal to the sum of its length sides
so

Part 2)
we know that
The area of triangle is given by the formula

we have

substitute

Answer:
The perpendicular bisector meets any line at an angle which is not 90°
Step-by-step explanation:

Answer:
85.5 minutes
Step-by-step explanation:
The amount of an element that will remain after time t can be expressed as a function of initial amount N0, time t, and half life th as;
Nt = N0 × e^(-λt)
Where;
Decay constant λ = ln(2)/th, substituting into the equation;
Nt = N0 × e^(-ln(2)t/th)
We need to make t the subject of formula;
Nt/N0 = e^(-ln(2)t/th)
ln(Nt/N0) = -ln(2)t/th
t = ln(Nt/N0) ÷ -ln(2)/th
Given;
Initial amount N0 = 760g
Final amount Nt = 11 g
Half life th = 14 minutes
the nearest tenth of a minute, would it take the element to decay to 11 grams can be derived using the formula;
t = ln(Nt/N0) ÷ -ln(2)/th
Substituting the given values;
t = ln(11/760) ÷ -ln(2)/14
t = 85.5 minutes