Answer:
(2, - 3 )
Step-by-step explanation:
Given the 2 equations
2x - 3y = 13 → (1)
x + 2y = - 4 → (2)
Rearrange (2) expressing x in terms of y by subtracting 2y from both sides
x = - 4 - 2y → (3)
Substitute x = - 4 - 2y into (1)
2(- 4 - 2y) - 3y = 13 ← distribute and simplify left side
- 8 - 4y - 3y = 13
- 8 - 7y = 13 ( add 8 to both sides )
- 7y = 21 ( divide both sides by - 7 )
y = - 3
Substitute y = - 3 into (3) for corresponding value of x
x = - 4 - 2(- 3) = - 4 + 6 = 2
Solution is (2, - 3 )
Answer:
x ≥ 54
Step-by-step explanation:
x+x-4 ≥ 104
2x ≥ 104 + 4
2x ≥ 108
x ≥ 54
Separate the variables:

Separate the left side into partial fractions. We want coefficients a and b such that





So we have

Integrating both sides yields






With the initial condition y(0) = 1, we find

so that the particular solution is

It's not too hard to solve explicitly for y; notice that

Then





