Answer:
(- 4, 1 )
Step-by-step explanation:
Given the 2 equations
y = x + 5 → (1)
x - 5y = - 9 → (2)
Substitute y = x + 5 into (2)
x - 5(x + 5) = - 9 ← distribute and simplify left side
x - 5x - 25 = - 9
- 4x - 25 = - 9 ( add 25 to both sides )
- 4x = 16 ( divide both sides by - 4 )
x = - 4
Substitute x = - 4 into either of the 2 equations and evaluate for y
Substituting into (1)
y = - 4 + 5 = 1
Solution is (- 4, 1 )
Answer:
I'd assume 7 times x, or 7x
Step-by-step explanation:
Algebraic phrases don’t include the equal sign and based on the information you gave me, I think 7x is the answer.
Lagrange multipliers:







(if

)

(if

)

(if

)
In the first octant, we assume

, so we can ignore the caveats above. Now,

so that the only critical point in the region of interest is (1, 2, 2), for which we get a maximum value of

.
We also need to check the boundary of the region, i.e. the intersection of

with the three coordinate axes. But in each case, we would end up setting at least one of the variables to 0, which would force

, so the point we found is the only extremum.