The value of b^2-4ac is known as the discriminant of a quadratic function, and can tell you how many roots exist of this function depending on what it is equal to.
Start by moving the -1 to the other side, as we need this function to equal zero.
2x^2 + 3x + 1 = 0
This is now the standard form ax^2 + bx + c = 0. Plug each value that corresponds into the discriminant equation.
b^2-4ac
(3)^2 - 4(2)(1)
9 - 8
1
The value of the discriminant is 1, meaning that two real roots exist for the function described.
Steps: for an approximate result, multiply the fuel economy value by 2.352
12.7*2.352=29.87
Answer: 29.87 Miles per Gallon
Given:
price = 1,250
sales discount = 15%
sales tax = 6.5%
The problem is unclear whether the price is the original price or the discounted price. I am assuming that the price is the original price.
Original price times sales discount rate is the value of sales discount
1,250 x 15% = 187.50
Original price less the value of sales discount is the discounted price.
1,250 - 187.50 = 1,062.50
Discounted price times sales tax rate is the value of the sales tax
1,062.50 x 6.5% = 69.06
Discounted price plus sales tax is the total cost of the purchase
1,062.50 + 69.06 = 1,131.56
That would be zero.
Obtuse means more than 90 degrees. A triangle's angles add up to 180 degrees so can't have two obtuse angles.