Answer:
If all angles in a quadrilateral are right angles, then it’s a rectangle (reverse of the rectangle definition). (Actually, you only need to show that three angles are right angles — if they are, the fourth one is automatically a right angle as well.)
If the diagonals of a parallelogram are congruent, then it’s a rectangle (neither the reverse of the definition nor the converse of a property).
If a parallelogram contains a right angle, then it’s a rectangle (neither the reverse of the definition nor the converse of a property).
Tip: Do the following to visualize why this method works: Take an empty cereal box and push in the top flaps. If you then look into the empty box, the top of the box makes a rectangular shape, right? Now, start to crush the top of the box — you know, like you want to make it flat before putting it in the trash. As you start to crush the top of the box, you see a parallelogram shape. Now, after you’ve crushed it a bit, if you take this parallelogram and make one of the angles a right angle, the whole top has to become a rectangle again. You can’t make one of the angles a right angle without the other three also becoming right angles.
Step-by-step explanation:
Answer:

Step-by-step explanation:
Assuming that the tank is only for agricultural use, also no significant leakages then at the end of the day, the amount consumed will be equivalent to 
For 5 days, the quantity reduces by 9.5*5=47.5 gallons
Therefore, the barrel would have changed by 
Move the decimal 2 places to the left.
Answer:
Casey Bought 6 bags of chips
Step-by-step explanation:
If each sandwich costs 3 times the amount of a bag of chips and the sandwich is 6 dollars, the chips are 2 dollars. Casey bought 5 sandwiches and spent $30 dollars on sandwiches. Since the total was $42 dollars you have $12 dollars left to get your total of $42. 2x6 = 12 so therefore Casey bought 6 bags of chips.