Question

Which equation is quadratic in form?

6(x + 2)2 + 8x + 2 + 1 = 0
6x4 + 7x2 – 3 = 0
5x6 + x4 + 12 = 0
x9 + x3 – 10 = 0

Answer 1

Option A

Explanation:

Did the test

Answer 2

we know that

A quadratic equation is a polynomial with an order of two. Its general form is

`ax^(2) + bx + c = 0`

case a)
`6(x + 2)^(2) + 8x + 2 + 1 = 0`

`6(x + 2)^(2) + 8x + 2 + 1 = 0 \\ 6(x^(2) +4x+4)+8x+3=0\\ 6x^(2) +24x+24+8x+3=0\\ 6x^(2) +32x+27=0\\\\ a=6\\ b=32\\ c=27`

The case a) is a quadratic equation

case b)
`6x^(4) + 7x^(2) - 3 = 0`

The case b) is a grade
`4` polynomial

case c)
`5x^(6) + x^(4) + 12 = 0`

The case c) is a grade
`6` polynomial

case d)
`x^(9) + x^(3) - 10 = 0`

The case d) is a grade
`9` polynomial

therefore

the answer is

`6(x + 2)^(2) + 8x + 2 + 1 = 0`