A+b=82
2a+4b=324
Solve for a and b. a is the # of borogoves, b is the # of mome raths.
Answer:
x=1 y=-5
Step-by-step explanation:
7(5x-2y=15) ---> 35x-14y=105
2(7x+7y=-28) --> + <u>14x+14y=-56</u>
49x=49 --->x=1
5(1)-2y=15 ---> 5-2y=15 ---> -2y=10 ---> y=-5
The procedure is to make the difference of the terms that occupy the same position (column and row):
| - 6 - 4 | | - 5 5 | | - 6 + 5 - 4 - 5 | | -1 - 9 |
| 6 0 | - | - 4 -1 | = | 6 + 4 0 + 1 | = | 10 1 |
| 6 4 | | 6 - 4 | | 6 - 6 4 + 4 | | 0 8 |
Answer: option B.

Common difference of an Arithmetic progression can be found out by subtracting the preceding term from that given term.
i.e
therefore, the common difference of the above Arithmetic progression is -4 .