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:
x=2
Step-by-step explanation:
use distributive property: x^2+2x-1=4
remove the -1 by adding 1 on both sides: x^2+2x=5
use the guadratic fromula: ax²+bx+c=0
plug in the equation x^2+2x-5=0
a,b and c are the coefficients to plug into the formula
a=1, b=2, c=-1
Finally, you will find that x=2
A 12-sided die is rolled. The set of equally likely outcomes is {1,2,3,4,5,6,7,8,9,10,11,12}. Find the probability of rolling
UNO [17]
1/6 is the probability of rolling a dice and getting less than 3.
Answer:
Step-by-step explanation:
Note that this function is not defined at x = 0; it does have a vertical asymptote which is the line x = 0, as well as a horiz. asymptote which is the line y = 0. This function is odd because the power of x is -1 (a negative odd number). Half the graph appears in Quadrant I: (1, 1), (2, 1/2), (3, 1/3), etc.
The other half is the reflection of the Quadrant I part in the origin, and this is because the function is odd.
Answer:
2,143.57
Step-by-step explanation:
The equation for volume of a sphere is 4/3 x pie x r^3. Plug in 8 for r = 512. 512 x 3.14= 1,607.68. 4/3 x 1,607.68 is about 2,143.57
