The answer is 90, 25, 155, 115 respectively
Answer:
Step-by-step explanation:
Like your other question, let's break it down systematically
6x + 9y - 9(6x - 3y + 8z)
Use the distributive property
6x + 9y - <u>9(6x - 3y + 8z)</u>
6x + 9y - 54x - 27y + 72z
Match like terms
6x - 54x = -48x
9y - 27y = -18y
72z - 48x - 18y
Duration, time taken, the completion time