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.
Hi there! :) The answer to your question is 3. First you do parenthesis r=3.
3+7=10, then you do 10*2=20. That is how you solve the problem.
Hope I helped! :)
( Mark as Brainliest Answer! Thank you! :)
Answer:
5. 57 9. 63
Step-by-step explanation:
Im Smart
With amounts measured in gallons, let
x = amount of 65% antifreeze
y = amount of 90% antifreeze
1 gal of the 65% brand contains 0.65 gal of pure antifreeze; x gal would contain 0.65x gal. Similarly, y gal of the 90% brand contains 0.90y gal of pure antifreeze.
To obtain 120 gal of 80% antifreeze solution (which contains 0.80•120 = 96 gal of pure antifreeze), we must have
x + y = 120 … … … … … [total volume of antifreeze solution]
0.65x + 0.90y = 96 … [total volume of pure antifreeze]
Solve the first equation for y :
y = 120 - x
Substitute this into the second equation and solve for x :
0.65x + 0.90 (120 - x) = 96
0.65x + 108 - 0.90x = 96
0.25x = 12
x = 48
Solve for y :
y = 120 - 48
y = 72
