The answer to this would be x-(x+14)
Here's an explanation:
Let x represent the unknown number. The problem says that x has been decreased by the sum of x and 14. So, to put this in a form of an equation, it would be x-(x+14), since you have to do the addition first before you can subtract the two number since you don't know what x is. This equation is equal to -14 no matter what x is.
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.
Step-by-step explanation:
plase see it my step work solution
The first reaction represented is a decomposition reaction due to the fact the bonded pair are being split apart.
The second equation is a single displacement because the B and C have switched places, which is the only change making it a single displacement. If there had been another bond and A had also moved, it would be double.
The ordered pairs for the intercepts are as follows:
x intercept = 9/2
y intercept = -18
In order to find either of these you must put 0's in for the other variable. So, to find the x intercept, we start by putting 0 in for y.
y = 4x - 18
0 = 4x - 18
-4x = -18
x = 9/2
To find the y intercept, we put a 0 in for x.
y = 4x - 18
y = 4(0) - 18
y = 0 - 18
y = -18