Answer:
Each algebra book costs $60.
Step-by-step explanation:
A=bill for algebra books; S=bill for science books=A+$360
S+A=$3960 Substitute for S
A+$360+A=$3960 Subtract $360 from each side.
2A=$3600 Divide each side by 2.
A=$1800 The order for 30 algebra books cost $1800.
Individual book=A/30
individual book=$1800/30=$60 ANSWER: Each algebra book cost $60.
EDIT:
2x + 0.75 = 13
Add like terms
2x= 13-0.75
2x= 12.25
x= 12.25/2
x=6.125
You can buy 6 whole shirts with $0.25 left over
Hope this helps! A thanks/brainliest answer would be appreciated :)