Question

(2) Out of the following equations which one is not a quadratic equation ?
(A) x - 4x = 11 - x2 (B) x² = 4x (C) 5x2 = 90 (D) 2x - x=x-5​

Answer 1

Answer:

Option (A) x² + 4x = 11 + x²

Step-by-step explanation:

I believe your Question was,

"Out of the following equations which one is not a quadratic equation ?

(A) x² + 4x = 11 + x²

(B) x² = 4x

(C)5x² = 90

(D) 2x - x² = x² + 5 "

Now,

We must use trial and error method to find this, if we just look at it and say, we may be correct around 60% but to be on the safe side we must solve the equation, to find whether it is or not,

Now,

(A)

x² + 4x = 11 + x²

x² - x² + 4x = 11

4x = 11

Here the degree is 1, thus, it is not a Quadratic equation.

(Degree simply means the highest power of the x variable.)

We can stop here but to be safe let's do the rest as well.

(B)

x² = 4x

x² - 4x = 0

Here, the degree of the polynomial is 2, thus, it is a Quadratic equation.

(C)

5x² = 90

5x² - 90 = 0

Here also, the degree of the polynomial is 2, thus, it is a Quadratic equation.

(D)

2x - x² = x² - 5

2x = x² + x² - 5

2x² - 5 = 2x

2x² - 2x - 5 = 0

Here also, the degree of the polynomial is 2, thus, it is a Quadratic equation.

Thus, Option A is the the equation which is not Quadratic.

Hope it helped and you understood it........All the best