Answer:
69 seconds, or 1 minute and 9 seconds
Step-by-step explanation:
First make it a fraction, then divide numerator by denominator
Answer:
Put the equation in standard form by bringing the 4x + 1 to the left side.
7x2 - 4x - 1 = 0
We use the discriminant to determine the nature of the roots of a quadratic equation. The discriminant is the expression underneath the radical in the quadratic formula: b2 - 4ac.
b2 - 4ac In this case, a = 7, b = -4, and c = -1
(-4)2 - 4(7)(-1)
16 + 28 = 44
Now here are the rules for determining the nature of the roots:
(1) If the discriminant = 0, then there is one real root (this omits the ± from the quadratic formula, leaving only one possible solution)
(2) If the discriminant > 0, then there are two real roots (this keeps the ±, giving you two solutions)
(3) If the discriminant < 0, then there are two imaginary roots (this means there is a negative under the radical, making the solutions imaginary)
44 > 0, so there are two real roots
