You answer is 3 and here's why...
7x + 5 - 3x - 7 = 10
First you must collect like terms
And that gives us
4x - 2 = 10
Next you must simplify by removing additives
4x - 2 + 2 = 10 + 2
4x = 12
Now you must divide
4x/4 = 12/4
x = 3
Using a system of equations, it is found that since 20 child bikes and 6 adult bikes would require more testing than the allocated time, it is not possible to build this amount.
<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 c: number of child bikes.
- Variable a: number of adult bikes.
Each child bike requires 4 hours to build, as do each adult bike. The company has 100 hours of testing, hence:
4c + 4a = 100.
c + a = 25.
With 20 child bikes and 6 adult bikes in a week, we have that c = 20, a = 26, hence:
c + a = 26
20 child bikes and 6 adult bikes would require more testing than the allocated time, it is not possible to build this amount.
More can be learned about a system of equations at brainly.com/question/24342899
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