Answer:
Step-by-step explanation:
Answer in the attachment
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:
3.7
Step-by-step explanation:


Hope this helps

What's The Fixed Point? Well, Let's Assume X=0, this is our point.

OR

I'm unaware of the nature of the question, so here are some different ways a fixed point is found based on the merits of the question.
Answer:
x = 8°
y = 21°
Step-by-step explanation:
27 + 3y = 90
3y = 63
y = 21°
x + 8x + 18 = 90
9x = 72
x = 8°