Step-by-step explanation:

For every 10 degrees Celsius, degrees Fahrenheit goes up 18, so
10 degrees C is 50
20 degrees C is 68
30 degrees C is 86
40 degrees C is 104
-5/2 is equivalent to -2.5, and if you multiply 2.5 by 2 you get 5, and you have to have the negative, so add that to the 5 and you get -5. Hope this helps!
Answer:
x² + 3x - 28
Step-by-step explanation:
Each term in the second factor is multiplied by each term in the first factor
(x + 7)(x - 4)
= x(x - 4) + 7(x - 4) ← distribute both parenthesis
= x² - 4x + 7x - 28 ← collect like terms
= x² + 3x - 28