Answer:
9a+6b
Step-by-step explanation:
4a+7b+5a-b
First figure out the a's 4a + 5a = 9a
Then do b's (Remember, if there is no number by the letter then it is 1)
7b - 1b = 6b
So for this to be simplified the answer is 9a+6b
7x+6=3x-6
+6 +6
7x+12=3x
-3x -3x
4x+12=0
-4x -4x
divide both sides by -4 but you have to flip the sign.
-3>x
or
{x | x < -3}
The 4 litres of red has to be 2 parts of the mixture, so each part will be 2 litres. Therefore 3 parts of cream will be 6 litres and the one part of blue will be 2 litres.