Answer:
5 gallons of water must be added.
10 gallons to start with
adding 'x' gallons of water final volume = 10 + x
.9 (10) = amount of vinegar
.1(10) = amount of water
amount of vinegar before and after water addition is constant
.9(10) = .6(10+x)
9 = 6 + .6x
3 = .6x
x = 5 gallons of water to be added
(i truly hope i helped you
Option D. 2(n + 9) is the right answer
Step-by-step explanation:
The word problems are converted into mathematical problems to solve simply.
for the given problem
"two times the sum of a number and 9"
Let n be a number then
when there is and between two things they are performed first then next operation is performed so
the sum of a number and 9

Then
two times the sum of a number and 9

Hence,
Option D. 2(n + 9) is the right answer
Keywords: Mathematical notation
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Selections 2, 3, 5, 6 are polynomials.
1 and 4 are not. The coefficients don't have to be integers, but the powers of the variables need to be positive integers. In 1, you have x^-1. in 4, you have x^(1/2).
Answer:
x = 15
Step-by-step explanation:
angles 2 and 4 are supplementary so they add up to 180
2x + 10 + 4x + 80 = 180
6x + 90 = 180
6x = 90
x = 15