X+Y=10
XY=-300
Solve for one of the variables
X=10-Y
Plug into the other equation
Y(10-Y)=-300
Now, you have a quadratic...
-y²-10y+300=0
I would multiply everything by -1, so there's no coefficient on y²
y²+10y-300=0
And solve...
-10±√(100-4(-300))
----------------------------
2
Y=-5±5√(13)
Plug back onto original equation...
X+(-5±5√(13))=10
X±5√(13)=15
X=15±5√(13)
Note: There are 2 sets of answers, keep the negatives with the negatives, and the positives with the positives when dealing with the ±.
Answer:
f = 4d -400
Step-by-step explanation:
First, let's make some variables.
f = size of Falls Lake
d = size of Lake Drummond
d = (1/4)*f + 100
We can now rearrange the equation to find the size of Falls Lake.
d - 100 = (1/4)*f
4d - 400 = f
f = 4d - 400
Answer:
Step-by-step explanation:
<h2> </h2>
So the first one is correct which implies that the third one is also correct.
But these are not the only ones.
The last one is also correct.
Hope this helps.
r3t40
Answer:
First ans is true but second one is not the cotrect
one
