Answer:
42.3
Step-by-step explanation:
- Substitute in values
Answer:
7.25b+4.95m=55.70
Step-by-step explanation:
B=Books
M=Magazine
Answer:
32/5
Step-by-step explanation:
<span>SALES: 5x² + 2x – 80
</span>- COST: 5x² – x + 100
= ------------------
PROFIT: 0x²+3x-180
(+3x because we subtracted a negative (-x), which is called adding, similarly taking away 100 from negative 80 is -180.)
Checking:
5x² + 2x – 80
5(500)²+2(500)-80 = 1,250,920
5x² – x + 100
5(500)² – (500) + 100= 1,249,600
Profit = 1,250,920 - 1,249,600 = 1,320
0(500)²+3(500)-180 = 1,320 YAY! {:-)
Double Checking:
5x² + 2x – 80
5(5000)²+2(5000)-80 = 125,009,920
5x² – x + 100
5(5000)² – (5000) + 100= 124,995,100
Profit = 125,009,920 - 124,995,100 = 14,820
0(5000)²+3(5000)-180 = <span>14,820</span> YAY! {:-)
Answer:
D is our choice
Step-by-step explanation:
For the money part we get
4x+6y ≤55
For the gallons we get
x+y ≥9
I will use elimination so multiply the second equation by -4
Remember when multiplying by a negative, the inequality flips
-4x -4y ≤-36
Add the first equation and the last equation together to eliminate x
4x+6y ≤55
-4x -4y ≤-36
----------------------
2y ≤19
Divide by 2
2y/2 ≤19/2
y ≤9.5
Now we need to find x
x+y ≥9
Substitute y in
x+9.5 ≥9
Subtract 9.5 from each side
x+9.5-9.5 ≥9-9.5
x ≥-.5
Also 4x+6y ≤55
Let y=0
4x ≤55
Divide by 4
4x/4 ≤55/4
x ≤13.76
Two things
We cannot buy parts of a gallon so y ≤9, x<13
and x and y cannot be negative ( no selling drinks we are buying them) so x ≥0 ,y ≤0
0 ≤y≤9
0 ≤x≤13
Which points fits these requirements
A and C have y >9 so they are eliminated
B has y as negative so it is eliminated
D is our choice
