Respuesta :
Let a be the number of hours that Brian works at Job A in one week and b be the number of hours that he works at Job B .in one week
Since Brian worked 22 hours per week and he made $148.60, we can set the following system of equations:
[tex]\begin{gathered} a+b=22, \\ 6.10a+7.30b=148.60. \end{gathered}[/tex]Subtracting b from the first equation we get:
[tex]\begin{gathered} a+b-b=22-b, \\ a=22-b\text{.} \end{gathered}[/tex]Substituting the above equation in the second one we get:
[tex]6.10(22-b)+7.30b=148.60.[/tex]Applying the distributive property we get:
[tex]\begin{gathered} 6.10\times22-6.10\times b+7.30b=148.60, \\ 134.20+1.20b=148.60. \end{gathered}[/tex]Subtracting 134.20 from the above equation we get:
[tex]\begin{gathered} 134.20+1.20b-134.20=148.60-134.20, \\ 1.20b=14.40. \end{gathered}[/tex]Dividing the above equation by 1.20 we get:
[tex]\begin{gathered} \frac{1.20b}{1.20}=\frac{14.40}{1.20}, \\ b=12. \end{gathered}[/tex]Substituting b=12 in a=22-b we get:
[tex]a=22-12=10.[/tex]Answer:
