Answer:
She should have substituted y = 17 - 2x in the first equation
Step-by-step explanation:
3x + 4y = 33
2x + y = 17
y = 17 - 2x
3x + 4(17 - 2x) = 33
3x + 68 - 8x = 33
5x = 35
x = 7
y = 17 - 2(7)
y = 3
x = 7, y = 3
Only one solution
Answer:
Step-by-step explanation:
Question says that it uses 120 feet of fencing material to enclose three sides of the play area. This means there are 3 sides. Putting this into equation, we have something like this.
120 = L + 2W
Where
LW = area.
Again, in order to maximize the area with the given fencing, from the equation written above, then Width, w must be = 30 feet and length, l must be = 60
On substituting, we have
A = LW = (120 - 2W) W
From the first equation, making L the subject of the formula, we have this
L = 120 - 2W, which then we substituted above.
On simplification, we have
L = 120W -2W²
Differentiating, we have
A' = 120 - 4W = 0
Remember that W = 30
So therefore, L = 120 - 2(30) = 60 feet
Answer:
its the last answer, the $735
Step-by-step explanation:
#5 is very nicely and correctly done.
#7 says: "No matter what X may be, this function of it is always 9 more than 1/2 of X .".
That's a very powerful statement. Now you know that if X is ever 2, the function will be 1/2(2)+9 which is 10.
If X is ever zero, the function will be 1/2(0)+9 which is 9. If X is ever a cow, the function will be 1/2 of a cow, plus the number 9. Which makes no sense, but that's what the function says.
So, when X is -8, the function is 1/2 of -8, plus 9. Which is 5 ... the 'f' of -8.
Whatever X happens to be at the moment, just write that number in place of X in the function, and it'll show you the function of what X is.
f(a bazillion) = 1/2(a bazillion) + 9 .
f(a-28) = 1/2(a-28) + 9 (but simplify it)
