Hello,
y+9=(x-10)*(-2)
==>y=-2x+11
Answer D if you put an "+" betheen y and 9 !!!!!!
For this case we have the following system of equations:

To solve, we clear "x" from the second equation:

We substitute "x" in the first equation:

We clear the value of the variable "y":

We look for the value of the variable "x":

Thus, the solution of the system is given by:

Answer:

Option D
Step 1: Find the Lowest Common Multiple between the denominators.
Step 2: Multiply the numerator and denominator of each fraction by a number (the one that will get them to the lcm) so that they have the LCM as their new denominator.
Step 3: Add or subtract the numerators and keep the denominator the same.
Find difference i.e 100-82=18
if 82 is 100%, what about 18?
(18*100)/82= 21.951 ans