Answer:
i’m pretty sure the first one is none of the above, the second is whole i’m pretty sure
Step-by-step explanation:
Answer:
a=1
Step-by-step explanation:
Subtract 9 on both sides
Subtract 3a on both sides
Then divide both sides by 3

You can get this by using the quadratic equation with a = 7, b = -1, c = -9
Answer:
(Thermometer B reading - Thermometer A reading)
Step-by-step explanation:
The thermometer reading aren't given in the question.
However, hypothetically.
The difference between two temperature values (morning and evening values) would be :
Temperature in the evening - morning temperature
Therefore,
If ;
Thermometer A reading = morning temperature
Thermometer B reading = evening temperature
Difference in the temperature :
(Thermometer B reading - Thermometer A reading)