Let x=ab=ac, and y=bc, and z=ad.
Since the perimeter of the triangle abc is 36, you have:
Perimeter of abc = 36
ab + ac + bc = 36
x + x + y = 36
(eq. 1) 2x + y = 36
The triangle is isosceles (it has two sides with equal length: ab and ac). The line perpendicular to the third side (bc) from the opposite vertex (a), divides that third side into two equal halves: the point d is the middle point of bc. This is a property of isosceles triangles, which is easily shown by similarity.
Hence, we have that bd = dc = bc/2 = y/2 (remember we called bc = y).
The perimeter of the triangle abd is 30:
Permiter of abd = 30
ab + bd + ad = 30
x + y/2 + z =30
(eq. 2) 2x + y + 2z = 60
So, we have two equations on x, y and z:
(eq.1) 2x + y = 36
(eq.2) 2x + y + 2z = 60
Substitute 2x + y by 36 from (eq.1) in (eq.2):
(eq.2') 36 + 2z = 60
And solve for z:
36 + 2z = 60 => 2z = 60 - 36 => 2z = 24 => z = 12
The measure of ad is 12.
If you prefer a less algebraic reasoning:
- The perimeter of abd is half the perimeter of abc plus the length of ad (since you have "cut" the triangle abc in two halves to obtain the triangle abd).
- Then, ad is the difference between the perimeter of abd and half the perimeter of abc:
ad = 30 - (36/2) = 30 - 18 = 12
Answer:
y=ln(x/(1-x))
Step-by-step explanation:
y=e^x/(1+e^x)
Cross multiply
y(1+e^x)=e^x
Distribute
y+ye^x=e^x
Put anything with x on with side and everything without x on opposing side:
y=e^x-ye^x
Factor right hand side
y=(1-y)e^x
Divide both sides by (1-y)
y/(1-y)=e^x
Use natural log.
ln(y/(1-y))=x
The inverse is
y=ln(x/(1-x))
So we are given the expression:
÷ 
When we divide fractions, we must flip the second term and change the sign to multiplication:
And then we multiply across:
Then we can break apart all of the like variables for simplification:
When we simplify variables through division, we subtract the exponent of the numerator from the exponent of the denominator. So we then have:
So then we multiply all of these simplified parts together:
So now we know that the simplified form of the initial expression is: 
.
24
Perimeter is amount out all sides added together.
Answer:
It is the tenths place. 109.7 is greater than 109.6
