Let's say x = 15% copper and y = 75% copper
We need 120 kg of a 51% copper alloy.
A) x + y = 120
B) .15x + .75y = 61.2 (which is 120*.51%)
Multiplying A by -.15
A) -.15x -.15y = -18 Then add this to B
.60y = 43.2
y = 72
x = 48
I'd suggest you look at this web page
http://www.1728.org/mixture.htm
***************************************
Double Check
48 kilograms of .15% copper = 7.2 kg copper
72 kilograms of .75% copper = 54 kg kg copper
So we have 61.2 kg of copper in 120 kg
61.2 / 120 = .51 = 51%
<u>Answer:</u>
The value of cos 45 degrees in simplified radical form is 0.70710 approximately.
<u>Solution:</u>
Given, Cos of angle 45 degrees.
We have to find the value of the Cos of 45 degrees in radical form.
From trigonometric ratios,
Cos of angle 45 degrees = cos 45 = 
Multiplying numerator and denominator with square root of 2

The value of square root of 2 is 1.414213

Hence, the value of Cos of angle 45 degrees is 0.70710 approximately
Answer:
Step-by-step explanation:1
Answer:

Step-by-step explanation:
The area of a rectangle is given by
where
is the length of the rectangle and
is the width of the rectangle. Therefore, based on the information given, we can write the following equation to solve for the width:
.
The perimeter of a rectangle is given by
. Therefore, the perimeter of the rectangle is:
.
Answer:
hieght at left is 24+1
and right is 25 both are equal now so h=25
base=8
area of triangle 1/2×b×h
1/2×8×25=100