It would be a rotation I believe
Answer:
x=3
y=3
Step-by-step explanation:
x = 6-y
-plug in (6-y) into first equation
2(6-y)+3y = 15
12-2y+3y=15
-2y+3y = 3
y=3
x=6-3
x=3
double check:
(2*3) + (3*3) = 6 + 9 = 15
3 + 3 = 6
You Just want to get Fahrenheit alone on one side of the equal sign. Your teacher forgot to use parenthesis. The correct equation for Celsius to Fahrenheit is:
Which will give you a completely different answer.... 
****
We will solve it using what is given:
C = (5/9)F - 32
C + 32 = (5/9)F
9(C + 32) = 5F
(9/5)(C + 32) = F
** If they mark you wrong, and try to say the answer is F = (9/5)C + 32 then they shouldn't be teaching math, and you should point out the fact there are no parenthesis around the F - 32 in the given formula.
Understandable- have a good day