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:
We conclude the equation is linear because it can be rewritten in the form
.
Hence, option D is correct.
Step-by-step explanation:
The slope-intercept form of the line or linear equation
where
is the slope
is the y-intercept
<u>Important Tip:</u>
The graph of a linear equation is always a straight line.
Convert the given equation in the slope-intercept form

subtract 18x from both sides

simplify

divide both sides by 9

Now, comparing the equation
with a slop-intercept form of linear equation
- The y-intercept b = -416/9
Therefore, we conclude the equation is linear because it can be rewritten in the form
.
From the attached graph, is also clear that the graph of the equation
is a straight line.
Hence, option D is correct.
Use pythagorena theorme
D=

NOTE: x1 and x2 means the first x and second x, not x^1 and x^2
points given are
(1,1)
(5,6)
x1=1
y1=1
x2=5
y2=6
D=

D=

D=

D=

6.403
answer is B
Answer:
21.2
Step-by-step explanation: