Answer:
0
Step-by-step explanation:
Answer:
<u><em>y=7 </em></u><u>number of hours at grocery store</u>
<u><em>x=18 </em></u><u>number of hours at baby- sitting</u>
Step-by-step explanation:
According to the information provided.
x is number of hours at baby- sitting
y is number of hours at grocery store
total number of hours worked
<em>1) </em><em>x+y =25</em>
total earn in a week
<em>2) </em><em>x*$6 + y* $9 = $171</em>
<em />
<em>from equation 1</em>
x+y=25
x= 25-y
<em>we place the above derived equation in equation 2 </em>
x*$6 + y* $9 = $171
(25-y)*$6 + y* $9 = $171
(25*6) -6y +9y =171
150+3y=171
3y=171-150
3y=21
<u><em>y=7 </em></u><u>number of hours at grocery store</u>
x= 25-y
x= 25-7
<u><em>x=18 </em></u><u>number of hours at baby- sitting</u>
Answer:
B. and D.
Step-by-step explanation:
Let p be the prize of a pen and m the prize of a mechanical pencils. If you buy six pens and one mechanical pencil, you spend 6p+m. We know that this equals 9, because you get 1$ change from a 10$ bill.
Similarly, if you buy four pens and two mechanical pencils, you spend 4p+2m, which is 8$, because now you get a $2 change. Put these equation together in a system:

Now, if you multiply the first equation by 2, the system becomes

Subtract the second equation from the first:

Plug this value into the first equation to get
