Answer:
6kg pure copper and 30 kg 10% copper was mixed to give 36kg of 25% alloy
Step-by-step explanation:
Here, we want to produce 36 kg of 25% alloy
Let the Pure copper be x kg while 10% alloy be y kg
Pure copper is simply 100% copper
Thus;
x + y = 36 •••••(i)
Then;
100% of x + 10% of y = 25% of 36
= x + 0.1y = 9 •••••• ii)
From i x = 36-y
from ii, x = 9-0.1y
Equate both x
36-y = 9-0.1y
36-9 = 0.1y + y
0.9y = 27
y = 27/0.9
y = 30
x = 36-y
x = 36-30
x = 6 kg
The function that has a vertex on the y-axis is f(x) = (x - 2)(x + 2)
<h3>How to determine the function?</h3>
For a function to have its vertex on the y-axis, then the coordinate of the vertex must be:
(h,k) = (0,y)
A quadratic function is represented as:
f(x) = (x - h)^2 + k
So, we have:
f(x) = (x - 0)^2 + k
Evaluate
f(x) = x^2 + k
From the list of options, we have:
f(x) = (x - 2)(x + 2)
Expand
f(x) = x^2 - 4
Hence, the function that has a vertex on the y-axis is f(x) = (x - 2)(x + 2)
Read more about vertex at:
brainly.com/question/18797214
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Answer:
4.2%
Step-by-step explanation:
percent error = (estimated value - actual value)/(actual value) × 100%
Here, the estimated value is 250 g, and the actual value is 250 g.
percent error = (estimated value - actual value)/(actual value) × 100%
percent error = (250 g - 240 g)/(240 g) × 100%
percent error = 10/240 × 100%
percent error = 0.041666... × 100%
percent error = 4.2%
Answer:
b
Step-by-step explanation:
a x (b + c) = (a x b) + (a x c)
