Sorry don't remember the identities but
8. 32a + 29b
9. 35x +5y
10. 24r
6990.2 do you understand cuase you have to multipky the three by the twenty one then take a way the plus and minus signs then move the whole equation on the other side of the equal sign
First, we see how many photos can be printed in a minute. We do know that it can print 28 photos in 8 minutes.
To find how many photos it can print in 1 minute, we divide 28 by 8.
28÷8=3.5
The printer can print 3.5 photos per minute.
To see how many minutes it will take to print 35 photos, we divide 35 by 3.5.
35÷3.5=10.
It will take 10 minutes to print 35 photos.
Have a nice day! :)