Answer:
4
Step-by-step explanation:
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.
10/16 because you multiply 8x2 to get sixteen, the denominator you need. So whatever you do to the denominator, you do to the numerator. So 5x2 is 10. 10/16
Answer:
12
Step-by-step explanation:
First, you will have to use trigonometry. Since the side of the triangleis the opposite of the angle 53 and the hypotenuse, you will use sin.
Sin 53 degrees = opposite side / hypotenuse side.
The opposite side is x and the hypotenuse side equals 15.
sin53= x/15
15 ( sin 53 ) =x
x= 11.97953
Round
x=12
X² + mx + 14
If (x+2) one of the factors, we can write
14 = 2*7
m = 2+7= 9
x² +9x + 14 = (x+2)(x+7)
