Ijust need on math period. i need with-15+b=-9 and -104=8x and x-7=13 so if anybody could just me with my math ill be very happy u know like my little toutor

-15+b=-9, you would need to add 15 to both sides to cancel out the -15, so you would get b=6.

-104=8x, divide 8 by -104, you get x=-13, don't forget you are diving 8 by -104! The negative will stay.

x-7=13, add 7 to both sides to cancel out the -7, you would get x=20.

It’s b because vpt is the whole triangle and ptc isn’t

If i'm correct the answer is $15.97