Answer:
First mechanic worked 20 hours and second mechanic worked 5 hours
Step-by-step explanation:
Let the number of hours the first mechanic worked = 
Let the number of hours the second mechanic worked = 
Therefore, we can write 2 equations and then solve them simultaneously:


Rearranging the first equation: 
and substituting into the second equation to find
:


Now sub
into the first equation to find 

Therefore, first mechanic (a) worked 20 hours and second mechanic (b) worked 5 hours
The missing factor in the equation is -21
<h3>What is a distributive factor?</h3>
The Distributive Property introduces the multiplication operator an existing mathematical statement that involves the addition operator.
From the complete question, the equation is given as:

Where x represents the missing factor.
So, we have:

Remove brackets

Collect like terms

Evaluate the like terms

Divide both sides by -1

Hence, the missing factor in the equation is -21
Read more about the distributive property at:
brainly.com/question/2807928
Answer:
6√x
Step-by-step explanation:
9√x - 3√x = 6√x
Answer:
c
Step-by-stepc explanation: