Answer:
12
Step by Step Explanation:
f(n+1) = 2f(n) + 10
a = 2, k = 10
a + k = 2 + 10 = 12
18 kg of 15% copper and 72 kg of 60% copper should be combined by the metalworker to create 90 kg of 51% copper alloy.
<u>Step-by-step explanation:</u>
Let x = kg of 15% copper alloy
Let y = kg of 60% copper alloy
Since we need to create 90 kg of alloy we know:
x + y = 90
51% of 90 kg = 45.9 kg of copper
So we're interested in creating 45.9 kg of copper
We need some amount of 15% copper and some amount of 60% copper to create 45.9 kg of copper:
0.15x + 0.60y = 45.9
but
x + y = 90
x= 90 - y
substituting that value in for x
0.15(90 - y) + 0.60y = 45.9
13.5 - 0.15y + 0.60y = 45.9
0.45y = 32.4
y = 72
Substituting this y value to solve for x gives:
x + y = 90
x= 90-72
x=18
Therefore, in order to create 90kg of 51% alloy, we'd need 18 kg of 15% copper and 72 kg of 60% copper.
Answer:
Step-by-step explanation:
divide by 3: x^2 = 4
Think you can finish that off now?
Answer:
M=8 Y=-2
Step-by-step explanation:
this is the slope and b
Answer:
h = 55
Step-by-step explanation:
the sum of the 3 angles in a triangle = 180°
the 2 unknown interior angles = 180 - 2h ( straight angle ), hence
the sum of the 3 angles
180- 2h + 180 - 2h + 40 = 180
400 - 4h = 180 ( subtract 400 from both sides )
- 4h = - 220 ( divide both sides by - 4 )
h = 55
