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.
So m=2, wherever m is put a 2
5x2+2(2+8)+3
Then do bidmas
Brackets-
5x2+2x10+3
Multiplication-
10+20+3
Addition-
33
Answer:33
Answer: The third one is the correct answer.
Step-by-step explanation: If you do the count, you will see that the number of goats added five times is equal to the number of cows.
Answer: it is already in standard form
Step-by-step explanation: for example
To write a linear equation in standard form, move each variable term to the left side of the equation and simplify.
A
x+/-By=c and in this case it is 2x-8y=16
