Answer:
m=7/9
Step-by-step explanation:
-5(-5m+5)=-2m-4
25m-25=-2m-4
25m+2m=-4+25
27m=21
÷ 27 ÷ 27 (divide both sides)
m=7/9 or .777 (infinite)
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:
D 49.1
Step-by-step explanation:
Hope it helps
have a great day
Answer:
it does not because it would not pass the straight line test
Step-by-step explanation:
sorry if its wrong and btw your cute
