30(or x)-8=22 I don't know if that is one of the answers or not
Average speed = total distance divided by total time.
In the first part, the car covered 490 km in 7 hours, but I think you mistyped the second part (“then covers a speed of 90km”) and a critical piece is missing to find the total distance and time.
Answer:
7/4 or 1 3/4
Step-by-step explanation:
Think of 2 2/4 to be 10/4 because you need to multiply the 2 to the 4 which makes 8 and then add 2 to get 10/4.
When you get 10/4 subtract it with 3/4 to get 7/4.
You can leave it as 7/4 or 1 3/4.
Using a system of equations, it is found that Debbie worked 45 hours during the week.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
In this problem, the variables are:
- Variable x: Amount of hours worked by Juan.
- Variable y: Amount of hours worked by Debbie.
Juan and Debbie each earn 9 per hour at their "jobs", and earned a total of 765 for the week, hence:
9x + 9y = 765
Simplifying the expression by 9:
x + y = 85 -> x = 85 - y.
Debbie worked five hours more than juan during the week, hence:
y = x + 5.
Since x = 85 - y, we replace in the expression:
y = 85 - y + 5.
2y = 90.
y = 45.
Debbie worked 45 hours during the week.
More can be learned about a system of equations at brainly.com/question/24342899
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