It tells us that:
(-2,4)
(-1,3)
(1,6)
(3,5)
(4,8)
Look at (3,5) ... it tells us that x = 3 and y = 5
So y = 5
2y+3x-5x^2-g contains 4 terms that cannot be further simplified without know the values for the variables y, x, and g. Although 3x and -5x^2 contain the same variable x, since they have have different exponents, we can not directly add them together without knowing the value of x.
The answer is 4.
The change in temperature for 1 hour would be -5. hope this helps.
