12. On addition, you can just combine like terms.
2v^3+(-v^3)=v^3
-v+v cancels each other out
8+(-3)=5
So you have v^3+5
14 On subtraction, you have to remember to distribute the negative sign so after you do that you have:
4h^3+3h+1+5h^3-6h+2
Then you can combine like terms
4h^3+5h^3=9h^3
3h-6h=-3h
1+2=3
So you end up with:
9h^3-3h+3
Hope that helps and feel free to ask any questions.
Answer:
We know that:
Energy released by fusion of hydrogen in 1 liter of solution A = 7.6x10^10 J
Energy used daily in a certain family home = 3x10^4 J
(you did not write the units, so i suppose that are the same in both cases)
Then, if x is the number of liters of solution A used, the energy produced will be:
E(x) = x*7.6x10^10 J
And we want this equal to 3x10^4
then:
E(x) = x*7.6x10^10 J = 3x10^4 j
now we solve this for x.
x = (3x10^4 j)/(7.6x10^10 j) = 3.9x10^-7
Then you need to use 3.9x10^-7 L of solution a.
Completing the square
alrighty
minus 31 both sides
x²+12x=-31
take 1/2 of the linear coefient and square it
12 is the linear coefient
12/2=6, (6)²=36
add that to both sides
x²+12x+36=36-31
factor perfect square trinomial
(x+6)²=5
square root both sides, remember to take positive and negative root
x+6=+/-√5
so what you want to write is
x+6=√5 and
x+6=-√5
the solutions
minus 6 both sides
x=-6+√5 and -6-√5
The answer is 7.00=.75x+1.29
X represents number of bagels Nick can buy