Answer: 25
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Explanation:
If f(x) is an even function, then,
f(-x) = f(x)
for all x in the domain
Based on that, we can say f(-3) = f(3)
So,
y = -2*f(3) - 3*f(-3)
y = -2*f(3) - 3*f(3)
y = -2*(-5) - 3*(-5)
y = 10 + 15
y = 25
