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
Answer:
CDF is scaled down by a factor of 1/2 of ABC
Step-by-step explanation:
Answer:
he needs to know the width!!!
Step-by-step explanation:
since length multiplied by the width equals area,
so since the length is given, the width is needed
Answer:
x= -8 BDC= 68
EXPLANATION:
They create a straight angle which is always equal to 180. this means you must add both equations and set them equal to 180.
The correct answer maybe
Actually I don't understand ur question