Question

Select all of the following that are quadratic equations.

7x^2 + 14x = 0
x^3 - 3x^2 + 1 = 0
5x - 7 = 0
x^2 + 3x -5 = 0
x - 5 = 9x + 7
x^2 - x = 3x + 7

Answer 1

• 7x^2 + 14x = 0
• x^2 + 3x -5 = 0
• x^2 - x = 3x + 7

Explanation:

In order, the highest degree of the variable x in these equations is ...

2, 3, 1, 2, 1, 2

The equations having a highest degree of 2 are quadratic equations.