Answer:

Step-by-step explanation:
Let
be the temperature on the first day
Second day temperature

Third day temperature

Fourth day temperature was 

On the first day the temperature was 
Answer:
what?
Step-by-step explanation:
For the 18 oz you pay $1.69 per oz and for 21 oz you pay $1.64 per oz so 21 oz for 12.81 is technically the better buy but the difference in price per ounce is so small that you should buy the size that suits your needs better.
Answer:
Step-by-step explanation:
If A is 170 less than B, than the equation for that is:
A = B - 170 (1) where the word "is" means equals and less than is subtraction.
If the total of A + B is 1520, then
A + B = 1520 (2). Sub equation (1) into equation (2):
(B - 170) + B = 1520 and
2B - 170 = 1520 and
2B = 1690 so
B = 845. Building B is 845 feet tall and Building A is
A = 845 - 170 (this is equation (1) with the height of B subbed in) so
A = 675 feet
675 + 845 should equal 1520 according to our equation. And of course it does.