Okay, so this is just a basic multiplication problem. first, we need to divide to figure out how much the trout population grows after 1 year. If it doubles in 4 years, then it will rise by a quarter each single year. So to put that in terms of fractions, then for every year, the equation would be 250x1/4. So then we do the equation, coming up with 62.5. This means that the population rises roughly 63 fish a year. So after 1 year, you will have roughly 313 fish. (312.5 to be exact). Then to get that by ten years, we can just multiply the number that we got for one year by ten. 62.5x10=625. So then we add the 250 original trout, and 250+625=875. So after 10 years, there will be 875 trout.
Call the two equations above A and B, in order to not confuse them.
A: -2x + 6y = -38
B: 3x - 4y = 32
For this system we have opposites in x and y, so Elimination (or Linear Combination) works best. Either variable works, so let's work with x first and multiply A by 3 and B by 2. This is done so we get opposites in A and B then when added together give zero.
-2x + 6y = -38 ------> multiply by 3 ----> -6x + 18y = -114
3x - 4y = 32 ------> multiply by 2 -----> 6x - 8y = 64
Now we add the new equations. The -6x and 6x are opposites and go away. We are left with
10y = -50. We divide both sides by 10 and get that y = -5.
Now we take y = -5 and put it into an original equation. Let's use A.
-2x + 6y = -38 the original equation A
-2x + 6(-5) = -38 we found y = -5
-2x + (-30) = -38 evaluating and multiplying
-2x - 30 = -38 apply the parentheses
-2x = -8 add 30 to both sides
x = 4 divide on both sides by -2
Thus x = 4 and y = -5, or (4, -5) is the solution.
Ok so there are 1000 meters in a kilogram right so
9000 meters= 9 kilograms
Answer:

Step-by-step explanation:
given that the side of the square is 4a
The expression for the area can be solved by
1. subtracting 5 from the sides of the square i.e (4a-5)
2. Solving for the area of the square using


opening the bracket and expending we have

the expression is 
The answer is 0 because 2+5 is 7 and then 5-2 is 7