Answer:
Step-by-step explanation:
hello:
x²-4x=0 means : x(x-4)=0
x=0 or x-4=0
conclusion : x=0 and x= 4 ...answer : B
Let x = no. of 10 oz cups sold
Let y = no. of 14 oz cups sold
Let z = no. of 20 oz cups sold
:
Equation 1: total number of cups sold:
x + y + z = 24
:
Equation 2: amt of coffee consumed:
10x + 14y + 20z = 384
:
Equation 3: total revenue from cups sold
.95x + 1.15y + 1.50z = 30.60
:
Mult the 1st equation by 20 and subtract the 2nd equation from it:
20x + 20y + 20z = 480
10x + 14y + 20z = 384
------------------------ subtracting eliminates z
10x + 6y = 96; (eq 4)
Mult the 1st equation by 1.5 and subtract the 3rd equation from it:
1.5x + 1.5y + 1.5z = 36.00
.95x + 1.15y+ 1.5z = 30.60
---------------------------subtracting eliminates z again
.55x + .35y = 5.40; (eq 5)
Multiply eq 4 by .055 and subtract from eq 5:
.55x + .35y = 5.40
.55x + .33y = 5.28
--------------------eliminates x
0x + .02y = .12
y = .12/.02
y = 6 ea 14 oz cups sold
Substitute 6 for y for in eq 4
10x + 6(6) = 96
10x = 96 - 36
x = 60/10
x = 6 ea 10 oz cups
That would leave 12 ea 20 oz cups (24 - 6 - 6 = 12)
Check our solutions in eq 2:
10(6) + 14(6) + 20(12) =
60 + 84 + 240 = 384 oz
A lot steps, hope it made some sense! I hope this helps!! ;D
Answer:
since they are alternate exteriors, we put a equal sign
2x+78=5x+15
next we subtract 78 on both sides
2x+78-78=5x+15-78
2x=5x-63
then we subtract 5x on both sides
2x-5x=5x-5x-63
-3x=-63
after that we divide -3 on both sides
-3x/-3=-63/-3
and the answer is
x=21
Step-by-step explanation:
Answer:
Numbers are 14 and 8
Step-by-step explanation:
Let the 2 numbers be x and y.
Write 2 equations:
x + y = 22
x - y = 6
Solve by substitution:
x - y = 6
x = y + 6
Plug into the other equation:
(y + 6) + y = 22
2y + 6 = 22
2y = 16
y = 8
Plug into either equation:
x + 8 = 22
x = 14
Numbers are 14 and 8
Answer:
29
Step-by-step explanation:
