Answer:
(x+8)^2 - 60 = 0
Step-by-step explanation:
x^2 + 16x + 4 = 0
x^2 + 16x + 64 - 60 = 0
(x + 8)^2 - 60 = 0
1. Well, we know it cannot be either the last or second to last answer as the original amount of pollutant (when x=0) is 10 tons.
After 1 foot of pipe 8 tons of pollutant are left (x=1). 8 tons is 80% of the original amount of the pollutant present. So, each foot of pipe keeps 80% of the pollutant. Make sense?
2. Just plug in the point into each answer choice.
(2,4)
y= 0.5x+ 5
4=0.5(2)+5
4=6
which is not true therefore the first answer choice is incorrect.
y=0.5x -3
4=0.5(2)-3
4=1-3
4=2
which is not true therefore the first answer choice is incorrect.
y=0.5x-5
4=0.5(2)-5
4=-4
which is not true therefore the first answer choice is incorrect.
y=0.5x +3
4=0.5(2)+3
4=1+3
4=4
This is the correct answer.
For an instance, i stands for the money that you have, and b stands for the money that brother has.
An equation system based on the problem would be
i + b = 42 (equation 1)
i = 3b (equation 2)
Use substitution method to solve the problem
substitute 3b into i in the equation 1
i + b = 42
3b + b = 42
4b = 42
b = 42/4
b = 10.5
substitute the value of b into the equation 1
i = 3b
i = 3(10.5)
i = 31.5
You have $31.5 and your brother has $10.5
