Answer:
$19,720
Explanation:
Put the given numbers into the formula and do the arithmetic.
P = principal amount, $17,000
r = interest rate, 8% = 0.08
t = 2 years
"I" = P + Prt
I = $17000 + $17000·0.08·2 = $17000 +2720
I = $19,720
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I put "I" in quotes because the variable capital-I is usually used in this context to refer to the amount of interest paid, not the entire repayment amount. However, that is what your formula is. It works for what you want.