The answer will be 7x^2 + 5x
To find out one book you have to divide 65 by 5
65/5 = 13
The answer is $13 per book
5+(1/7)b=-2
First subtract 5 from both sides. Our goal is to isolate b.
5+(1/7)b-5= -2-5
(1/7)b= -7
Now multiply both sides by 7 because (1/7)*7= 7/7 or 1.
7* (1/7)b= -7*7
1b= -49
Final answer: b= -49
You should move the variable to the same side!
best by addition/substraction:
for example:
2x+5=3x
I will "move" the 3x:
2x+5-3x=0
now you can add up the variables: -x+5=0 (x=5)
essentially you can move it to the other side, changing the sign: + to -, - to +