6 nickels is 30 cents and 30 cents is 3/10 of a dollar which is 30% of a dollar.
The answer to this question is choice B. To complete the square, we take the coefficient on the x term, halve it, and then square it. This results in -9/2, and then 81/4. This value of 81/4 is added to both sides, allowing for factorization of the lefthand side of the equation.
It will be 93 because it 92 but you have to round up with deimal number
7 cm: 35000 cm (7*5000)
2.8 cm: 14000 cm (2.8*5000)
2 cm: 10000 cm (2*5000)