Step-by-step explanation:
The error carolyn has made is that she hasn't subtracted properly.
2x + 3y - (2x +6y) = 2x - 2x + 3y - 6y = -3y.
Carolyn probably didn't use parentheses...
To do the thing in substitution, we single out x or y in any equation. In this case, i'm gonna single out the x in the 2nd eqn. In other words, i'll make x the subject of the 2nd eqn.
2x + 6y = 10
2x = 10 - 6y
x = 5 - 3y
Now we simply plug in 5 - 3y wherever x apperas in the 1st equation.
2 (5-3y) + 3y = 8
10 - 6y + 3y = 8
10 - 3y = 8
-3y = -2
y = 2/3
Then x = 5 - 3*2/3 = 3
x=3
y=2/3
Hope it helps:)
Answer: 56-(7+5)
Step-by-step explanation:
You can find the amount of muffins left over by adding up the amount of muffins that were eaten and subtracting them from the original amount of blueberry muffins, so the answer is 56-(7+5).
(7+5 is in parentheses because if not, you would have 56-7+5 and get 54).
Answer:
It's C
Step-by-step explanation:
120 x 0.4 = 48
120 - 48 = 72