Step-by-step explanation:
2x - 3y = 9
2x + 3y = 3
__________ -
-6y = 6
y = -1
2x - 3y = 9
2x - 3(-1) = 9
2x - (-3) = 9
2x = 12
x = 6
F(x) = 112 - kx
f(-3) = 121
f(-3) = 112 - k(-3)
f(-3) = 112 + 3k
121 = 112 + 3k
121 - 112 = 3k
9 = 3k
9/3 = k
3 = k <===
√8 = √(4x2) = 2√2
4√2 =4√2
2√2-4√2 = -2√2
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