In system A, the first equation multiply by 4
8x - 4y = 12 (1st)
3x + 4y = 10 (2nd)
--------------------add
11x = 22
So answer is B.
To find average, add up the values given and then divide that number by the amount of values that you added to make the larger number.
For example:
If he ran -8 yards first and -6 yards second and they are asking you to find the average, add -8 and -6. You get -14. If you then divide by 2 because you added 2 numbers together, you end up with -7.
Hope this helps!
The answer to this question would be D. 3(x)-3(9)
It keeps going up by 2......3....4....5.... so the answer is easy, 15 + 6 = 21!
