What are we supposed to estimate??...
The answer is -10 and -13. when added they equal -23 and when you switch the symbol of the 10 and make the equation 10-13 you get -3. hope this helped.
-7x - 6y = 59.....multiply by -1
-8x - 6y = 58
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7x + 6y = -59 (result of multiplying by -1)
-8x - 6y = 58
---------------add
-x = -1
x = 1
-7x - 6y = 59
-7(1) - 6y = 59
-7 - 6y = 59
-6y = 59 + 7
-6y = 66
y = -66/6
y = -11
solution is (1,-11)