Answer:
See Explanation
Step-by-step explanation:
Your question is incomplete, as the equations or graph or table(s) were not given.
However, I'll give a general way of solving this.
Take for instance, the equations are:


To do this, we start by equating both equations.

i.e.

Collect Like Terms

Take LCM


Cross Multiply


Make x the subject

Substitute 3/4 for x in 



Hence:

%66.666
Because 4/6 times it will be that which is %66.666
Current temperature = -2°C
Rise in temperature = 15°C
New temperature = (-2 + 15)°C = 13°C