Answer: it’s D
Step-by-step explanation:
Answer: 18/5 hours, or 3.6 hours
=================================================
Work Shown:
x = amount of time it takes Blake to do the job by himself
y = amount of time it takes Ned to do the job by himself
z = time it takes if they worked together
In this case,
x = 9 and y = 6
Use those values to find z.

Distribute the two to each of the values in the parentheses.
-4 +6a-10= 1-1a
Then move like terms to the same side to simplify.
6a+1a=1+10+4
7a=15
a=15/7
Answer:
65 i think
Step-by-step explanation: