ok so i can’t answer all of them BUT!! if a=a: infinitely many, x=a: one solution, a=k: zero solutions. hope this helps!
you would change the denominators to the least common multiple, in this case, 12. then you would change the fractions to 8/12, 14/12, and 7/12. you would add those, and get 29/12. divide 29 by 12, and get 2. add the rest to get 2 5/12.
Answer:
Upper left is 9, upper right is 9, lower left is 21
Step-by-step explanation:
They tell us there are 9 birds that are yes fly and yes fish, so that’s the upper right.
They tell us there are 18 yes fish total. Subtract the 9 from the upper right, and that leaves 9 for the upper left.
They tell us there are 39 birds total.
39 - 18 (all fish eaters) - 4 (no fly, no fish) = 17 that can fly but don’t eat fish.
Make sense? lmk if you have questions