Multiply the first equation by 2
4x-6y=16
Then add the equations to eliminate x
4x-6y=16
-4x+5y=-10
-y=6
y-=6
Plug the y value in
2x-3(-6)=8
2x+18=8
2x=-10
x=-5
Final answer: (-5,-6)
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:
<h3>5</h3>
Step-by-step explanation:
Given the expression
2a^3−10ab^2+3a^3−ab^2−7
We are to find the coefficient of a^3
First is to collect the like terms;
2a^3−10ab^2+3a^3−ab^2−7
= 2a^3+3a^3−10ab^2−ab^2−7
= 5a^3-11ab^2-7
From the resulting equation, you can see that the coefficient of the term having a^3 is 5
Answer:
https://www.wikihow.com/Do-Long-Division
Step-by-step explanation:
Hope this helps! It goes into detail. Can you make me brainliest?
Answer: Second Option
(Point in Quadrant I)
Step-by-step explanation:
The solution to a system of linear equations is the point where the two lines intersect.
Note that in this case we have two lines with different slope . By definition, if two lines have different slopes and are contained in the same plane, then there will always be an intersection between them at some point in the plane.
Looking at the image, you can see that the lines get closer as x and y increase. Then they will intercept in the first quadrant.
