The answer is d.
Its is because dcf match up like a square and make a right angle.
Answer:
5
Step-by-step explanation:
Answer:
x = -7/3y + 8/3
y = -3/7x + 8/7
Step-by-step explanation:
First, set the equations next to each other to find x and y, I'll start with x:
x + 3y + 2x + 4y = 8
Combine like terms
3x + 7y = 8
Subtract both sides by 7y
3x + 7y - 7y = 8 - 7y
3x = 8 - 7y
I'll re-order the equation to make it easier to divide
3x = -7y + 8
Divide both sides by 3
3x / 3 = -7y + 8 /3
x = -7/3y + 8/3
If you need decimals just divide with a calculator
Now to find y:
We already combined like terms so we don't need to do that again...
3x + 7y = 8
Subtract both sides by 3x
3x - 3x + 7y = 8 - 3x
7y = 8 - 3x
I'll reorder the equation once again so the variable comes first
7y = -3x + 8
Divide both sides by 7
7y / 7 = -3x + 8 / 7
y = -3/7x + 8/7
Again, use a calculator to divide completely for decimals.
So the complete amount of fishes were 100%
70% died and 60 are left...
so 100% - 70% = 60
100% - 70% = 30%
30% = 60 fishes...
so 10% = 20 fishes
If you complete that percentage to 100
10% = 20, 100% 200