Answer:
<em>Cathy was born in 1980 and she was 18 years old in 1998</em>
Step-by-step explanation:
<u>Equations</u>
This is a special type of equations where all the unknowns must be integers and limited to a range [0,9] because they are the digits of a number.
Let's say Cathy was born in the year x formed by the ordered digits abcd. A number expressed by its digits can be calculated as
In 1998, Cathy's age was
And it must be equal to the sum of the four digits
Rearranging
We are sure a=1, b=9 because Cathy's age is limited to having been born in the same century and millennium. Thus
Operating
If now we try some values for c we notice there is only one possible valid combination, since c and d must be integers in the range [0,9]
c=8, d=0
Thus, Cathy was born in 1980 and she was 18 years old in 1998. Note that 1+9+8+0=18
9514 1404 393
Answer:
12.9 square yards
Step-by-step explanation:
The base is an equilateral triangle, so we can assume that the three faces have the same dimensions. Each of those face triangles has an area of ...
A = 1/2bh
A = 1/2(3 yd)(2 yd) = 3 yd²
The base area is computed using the same formula and the given height:
A = 1/2(3 yd)(2.6 yd) = 3.9 yd²
Then the total surface area is that of the base and the three faces:
SA = (3.9 yd²) + 3(3 yd²) = 12.9 yd² . . . total surface area
Answer: draw a straight line trough point B, same thing with the second one,for the third you must draw a straight line from the angle across to the segment. (make sure all of the intersections are 90 degrees
Answer:
n
Step-by-step explanation:
-12n - (-13n) = -12n +13n = 1n
Answer:
√(V / π × h), where V is the volume of the cylinder, h is the height, and π(Pi) is a mathematical constant with an approximate value of 3.14
