Answer:
Step-by-step explanation:
It is a linear homogeneous differential equation with constant coefficients:
y" + 4y = 0
Its characteristic equation:
r^2+4=0
r1=2i
r2=-2i
We use these roots in order to find the general solution:
Answer:
x+13=40 and the answer to that is 27
First, let's cancel out the x by multiplying 2x + 18y = -9 by -2.
-2 ( 2x + 18y = -9) = -4x -36y = 18
Then, we combine the two equations.
-4x + 4x = 0
18y - 36y = -18y
-27 + 18 = -9
Our new equation is -18y = -9.
Now, divide both sides by -18.
-18y / -18 = y
-9/ -18 = 1/2
y = 1/2
We can plug in a value for y since y = 1/2 now.
Let's use 2x + 18y = -9
Plug in y.
2x + 18(1/2) = -9
2x + 9 = -9
Then, subtract 9 from both sides.
2x = -18
Divide by 2.
2x/2 = x
-18/2 = -9
x = -9
Lastly, we can plug in both x and y values to see it works.
2(-9) + 18(1/2) = -9
-18 + 9 = -9
Therefore, the values of x and y does work.
x = -9
y = 1/2
Answer:
x = 3
y = 0
z = 8
Step-by-step explanation:
a) 3x + 3y - z = 1
b) z = 8
c) -x -3y + 2z = 13
a) 3x + 3y - 8 = 1 (substitution)
a) 3x + 3y = 9
c) - x - 3y + 2(8) = 13 (substitution)
c) -x - 3y + 16 = 13
c) -x - 3y = -3
(3x + 3y = 9) + (-x -3y = -3)
= 2x = 6
x = 3
a) 3(3) + 3y - 8 = 1
9 + 3y - 8 = 1
y = (1 -9 + 8)/3
y = 0
Answer:
Practice more and do you work
Step-by-step explanation:
