Answer: Answer is (D)
Step-by-step explanation:
I got the answer correct on Edg.
X + y = 15
Rearrange this to isolate for x.
x = 15 - y
x + z = 20
Rearrange this to isolate for x also.
x = 20 - z
Since they are both equal to x, that means they are equal to each other (x = x)
Set them equal to each other.
15 - y = 20 - z
Now, isolate for y.
y = 15 - 20 + z
Now, use y + z = 25 and isolate for y.
y = 25 - z
Since they are both equal to y, we set them equal to each other.
15 - 20 + z = 25 - z
Solve for z
z + z = 25 - 15 + 20
2z = 30
2z/2 = 30/z
z = 15
Now you can plug the value for z into the other equations to find y and x.
x + z = 20
x +15 = 20
x = 20-15
x = 5
y + z = 25
y + 15 = 25
y = 25 - 15
y = 10
It’s a question because there is not value of time.
ANSWER
The solution is
(x,y)=(1,-5)
EXPLANATION
The equations are:
1st equation: 6x +5y=-19
2nd equation: 12x-8y=52
Multiply the first equation by 2:
3rd equation: 12x +10y=-38
Subtracy the 2nd equation from the 3rd equations.
12x-12x+10y--8y=-38-52
18y=-90
Divide both sides by 18.
y=-5
Put y=-5 into any of the equations and solve for x.
Preferably, the first equation will do.
6x +5(-5)=-19
6x -25=-19
6x=25-19
6x=6
x=1
The solution is
(x,y)=(1,-5)
