Answer:
Use 49 ounces of the 14% allow and 41 ounces of the 23% alloy.
Step-by-step explanation:
Each ounce of the 14% copper contains 0.14 ounce of pure copper.
Each ounce of the 23% copper contains 0.23 ounce of pure copper.
Each ounce of the 18.1% copper contains 0.181 ounce of pure copper.
Use x ounces of the 14% and y ounces of the 23% to make 90 ounces of 18.1% alloy.
x+y = 90
y = 90-x
0.14x + 0.23y = 0.181·90
0.14x + 0.23(90-x) = 16.29
0.14x + 20.7 - 0.23x = 16.29
-0.09x + 20.7 = 16.29
4.41 = 0.09x
x = 49
y = 90-x = 41
Use 49 ounces of the 14% allow and 41 ounces of the 23% alloy.
Answer:
3^x + 12x -4
Step-by-step explanation:
f(x) = 3^x + 10x
g(x) = 2x - 4,
(f + g)(x) = 3^x + 10x + 2x - 4
Combine like terms
= 3^x + 12x -4
Answer:
15. -2 16. 0 17. undefined
Step-by-step explanation:
Slope of two points can be calculated by (y change) / (x change).
(y1 - y2) / (x1 - x2)
15) (1-5) / (4-2) = -2
16) (6-6) / (1-10) = 0 since y change is 0.
17) (-5-3) / (4-4) = undefined since x change is 0 but you cannot devide by 0.
Answer:
She had 15 minutes left.
Step-by-step explanation:
30 - 11 = 19
19 - 4 = <em>15</em>
Answer:
r = 8
Step-by-step explanation:
The common ratio r of a geometric sequence is
r = 
= 
= ..... = 
Then
r = 
= 
= 8
