Answer:
D. (4, -3)
Explanation:
You only need to find the value of y to select the correct answer, so if we're going to solve this system by elimination, we should choose to eliminate the x-variable.
We can subtract 3 times the first equation from 7 times the second to eliminate x. Those multipliers will give x-terms that will cancel.
3(7x +8y) -7(3x +2y) = 3(4) -7(6)
21x +24y -21x -14y = 12 -42 . . . . . eliminate parentheses
10y = -30 . . . . . . . . . . . . . . . . . . . . .collect terms
y = -3 . . . . matches choice D