Answer:
C
Step-by-step explanation:
all the options can give 9m+27 except C; 9m+12
Answer:
show a picture please i can still help you :3
Step-by-step explanation:
Answer:
12 because 1+2 add 1 to 2 WOW
Step-by-step explanation:
Answer:
Krista put 0.40 in the first equation meant for the number of stamps.
Step-by-step explanation:
Krista's equation
0.40x+y=45
x+0.55y=18.75
The system of Equation should have been
x + y = 45 (1)
0.40x + 0.55y = 18.75 (2)
From (1)
x=45-y
Substitute x=45-y into (2)
0.40(45 - y) + 0.55y = 18.75
18 - 0.40y + 0.55y = 18.75
Collect like terms and you now have
0.55y - 0.40y = 18.75 - 18
0.15y = 0.75
Divide both sides of the equation by 0.15
y = 5
Substitute y=5 into (1)
x + y = 45
x+5=45
x=45-5
x=40
This shows that the stamps that cost 0.40 cents were 40 while those that cost 0.55 cents were 5 in number.
Krista's error:
Krista put 0.40 in the first equation meant for the number of stamps.
1. 28
2. 2 7/12 or approximately 2.58
3. I believe 580 but I could be wrong.
4. 213.75