Answer:
6 2/3 minutes
Step-by-step explanation:
Their rates in "jobs per hour" are ...
(60 min/h)/(15 min/job) = 4 jobs/h
and
(60 min/h)/(12 min/job) = 5 jobs/h
So, their combined rate is ...
(4 jobs/h) + (5 jobs/h) = 9 jobs/h
The time required (in minutes) is ...
(60 min/h)/(9 jobs/h) = (60/9) min = 6 2/3 min
Working together, it will take them 6 2/3 minutes.
subtract them
593.7-573.36 = 20.34seconds
so c is the answer
X^2/(x- 9 = 81/(x - 9)
This is the equation for which you want the solution.
Multiplying both sides of the equation by (x - 9) we get
x^2(x - 9)/(x - 9) = 81(x - 9)/(x - 9)
So the (x - 9) goes out from both the denominator and the numerator and then the simplified equation becomes
x^2 = 81
x ^2 = (9)^2
x = 9
So the value of the unknown variable x comes out to be 9.
<h3>
Answer: 49</h3>
Work Shown:
Replace x with 3, replace y with -8. Use order of operations PEMDAS to simplify.
x^2 + y^2 + x*y
3^2 + (-8)^2 + 3*(-8)
9 + 64 - 24
73 - 24
49
The product of the expression
is the expression 
<h3>What is an
equation?</h3>
An equation is an expression that shows the relationship between two or more variables and numbers.
Given the expression:

The product of the expression
is the expression 
Find out more on equation at: brainly.com/question/2972832
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