Answer:
NO SOLUTION
Step-by-step explanation:
The value of cosines is between -1 and 1
As a result, it will never goes to -12 no matter what
Let a=2018, we can rewrite the question into

substitute back a = 2018, obtained

well, there is something wrong here
Y-10=2x -16
2x-y = -16+10
2x - y = - 6 ( ax + by = c )
You can read fractions as one number divided by another. So 1/6 is equivalent to 1 divided by 6. It is then selfevident that the larger the denominator the smaller the number. If you have one cake and divide it between 3, 6 or eight people, three people will get a larger slice than 6 people sharing the same cake. And 6 people will get a larger slice than 8 people dividing the same cake.