document.write( "Question 879530: 4. The polynomial function I(t) = -0.1t2 + 1.9t represents the yearly income (or loss) from a real estate investment, where t is time in years after 1970. During what year is the maximum income occur?
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Algebra.Com's Answer #530854 by ewatrrr(24785)\"\" \"About 
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I(t) = -.1(t - 9.5)^2 + 9.025
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