Using a simple guess and check method, i started with the lowest common multiple of 3, and 27 (the total growth) and used 3. if you plug i the numbers, we will say a is the dwarf lemon tree, b is the semi-dwarf lemon tree, and c is the full lemon tree, you know 3times2 equals 6. if you triple 6 you get 18. so if A grew 3 inches , B had to have grown 6 inches, and C had to have grown 18 inches. add them all and you get 27. so the dwarf lemon tree grew 3 inches, semi dwarf grew 6 inches, the full size grew 18 inches.
The last answer is correct
Distribute the -2 by multiplying it to 5x and -0.75
1/2x -9, you take half of x so multiply 1/2 times x then you subtract the 9 after due to PEMDAS ( parentheses, exponents, multiplication & division, Add & Subtract) you follow the order of operation starting with Parentheses and ending with adding or subtracting
-18
1) Distribute the -6 to the parentheses
-4 - (6*7) - (-6*3)
2) Simplify
-4 - 42 + 18
-18
Each song downloaded costs 3 points
each video costs 40 points
total of 999 points
if each song cost 3 points and she has 999 points to use she can download 333 songs at max