Respuesta :
Answer:
She worked 9 hours on store and gave piano lessons for 6 hours
Step-by-step explanation:
Let x be the no. of hours she worked on store
Cost of 1 hour on shop = $8.47
Cost of x hours on shop = $8.47x
Let y be the no. of hours she gave piano lessons
Cost of 1 hour for piano lessons = $17
Cost of y hours on shop = $17y
Now we are given that She worked for 15 hours
So, [tex]x+y=15[/tex] ---1
We are also given that she earned $178.23 between the two jobs
So, [tex]8.47x+17y=178.23[/tex] --2
Plot equation 1 and 2 on graph
Refer the attached figure
[tex]x+y=15[/tex] -- Blue line
[tex]8.47x+17y=178.23[/tex] -- Green line
Intersection point gives the solution .
Intersection point = (9,6)
So, x = 9 and y = 6
So, she worked 9 hours on store and gave piano lessons for 6 hours