How to use the quadratic formula | Polynomial and rational functions | Algebra II | Khan Academy

What is the primary use of the quadratic formula?

• To find the area of a triangle.

• To solve for the roots of quadratic equations.

• To calculate the perimeter of a square.

• To determine the volume of a cylinder.

Which of the following represents the general form of a quadratic equation?

• a + b + c = 0

• ax + b = 0

• ax^2 + bx + c = 0

• a^2 + b^2 = c^2

What is the quadratic formula used to find the value of 'x' in a quadratic equation?

• x = (b ± sqrt(b^2 - 4ac)) / 2a

• x = (-b ± sqrt(b^2 + 4ac)) / 2a

• x = (-b ± sqrt(b^2 - 4ac)) / 2a

• x = (b ± sqrt(b^2 + 4ac)) / 2a

For the quadratic equation x^2 + 4x - 21 = 0, what are the values of a, b, and c?

• a=1, b=4, c=21

• a=1, b=-4, c=-21

• a=1, b=4, c=-21

• a=0, b=4, c=-21

Which of the following is the correct quadratic formula?

• x = (-b ± sqrt(b^2 - 4ac)) / 2a

• x = (b ± sqrt(b^2 - 4ac)) / 2a

• x = (-b ± sqrt(b^2 + 4ac)) / 2a

• x = (-b ± sqrt(b^2 - 2ac)) / a

In the quadratic equation ax^2 + bx + c = 0, which term represents the 'a' coefficient?

• The constant term

• The coefficient of x

• The coefficient of x^2

• The exponent of x

What is the value of the discriminant (b^2 - 4ac) for the equation 3x^2 + 6x + 10 = 0?

• 36

• 120

• -84

• 84

What does it mean if the discriminant (b^2 - 4ac) of a quadratic equation is a negative number?

• There are two distinct real solutions.

• There is exactly one real solution.

• There are no real solutions.

• There are infinitely many solutions.

In the quadratic equation -3x^2 + 12x + 1 = 0, what is the value of the coefficient 'a'?

• -3

• 12

• 1

• 0

What is the value of the discriminant (b^2 - 4ac) for the equation -3x^2 + 12x + 1 = 0?

• 144

• 12

• 156

• 132