Answer: x =(3-√157)/2=-4.765
x =(3+√157)/2= 7.765
Step-by-step explanation:
You do 304 subtract 217 which equals 87
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

Answer:
3x + 3y
Step-by-step explanation:
The two minus signs make a plus sign. Therefore, we replace the minus signs with a plus sign, getting 3x + 3y.