Final answer:
To simplify the expression, we need to combine like terms and perform the operations in the correct order. After combining the like terms and simplifying the fraction, the expression simplifies to -3.6.
Step-by-step explanation:
To simplify the given expression, -3/5 * k - 9 + 6 + 1/4 * k - 7/20 * k - 3 * 7/20 * k - 3 * -2/9 * k - 15 * -17/20 * k - 15, we need to combine like terms and perform the operations in the correct order.
First, let's multiply the coefficients by their respective variables: -3/5 * k = -3k/5, 1/4 * k = k/4, -7/20 * k = -7k/20, -3 * 7/20 * k = -21k/20, -3 * -2/9 * k = 2k/3, -15 * -17/20 * k = -255k/20.
Next, let's combine the like terms: -3k/5 - 7k/20 - 21k/20 + 2k/3 - 255k/20.
Now, let's combine the coefficients: -3/5 - 7/20 - 21/20 + 2/3 - 255/20 = -216/60.
Finally, let's simplify the fraction: -216/60 = -3.6.
Therefore, the simplified expression is -3.6.