Answer:
Ethan's balance at the end of the week is of $273.75.
Step-by-step explanation:
Ethan starts the week with a balance of $275.00 in his checking account.
This means that B = 275.
During the week, he uses his debit card to spend $27.50 on food, $12.00 at the movies, and $6.75 for music downloads.
This is subtracted from the balance. So
B = 275 - (27.50 + 12 + 6.75) = 228.75
He earns and deposits $45.00 for mowing lawns.
Adds 45, so
B = 228.75 + 45 = 273.75
Ethan's balance at the end of the week is of $273.75.
The answer depends on what is meant by the "fourth term". By the binomial theorem, one answer could be

By symmetry, another could be
Yes, they are congruent. Congruent means that they are exactly equal in size and shape. The are both Right Triangles (you can tell by the 90 degree angle) and the lines on them are in the same spots, which means, line YZ is equal to line BC, and that line XZ is equal to line AC. I hope that helped! :)
(-2) + 6 + 1 = 1 + 6 + (-2)
-2 + 7 = 7 - 2
5 = 5
It looks like it's just the second one, but idk. They all seem too specific for a random card guess besides #2.