Question

22) If2 times of a positive whole number is less
by 1 than thrice of its square, then find the
number.​

Answer 1

Answer:

The answer will be 1.

Step-by-step explanation:

Let the the positive whole number be some variable (any alphabetical term), lets say, x.

Then according to question;

                 ⇒ 2(positive whole number) + 1 = 3 (positive whole number)^2

                 ⇒2 (x) + 1 = 3 (x)^2;

                 ⇒2x + 1 = 3x^2;

  Now, we'll transpose the R.H.S to L.H.S;

thus,          ⇒ 2x + 1 - 3x^2= 0;

Now, multiply (-1) on both side;

                 ⇒ (-1)(2x + 1 - 3x^2) = 0 * (-1);

                 ⇒  3x^2 -2x - 1 = 0;

Here, we'll use splitting method of finding the two factors;

                ⇒   3x^2 - 3x + x - 1 = 0;

                ⇒ 3x (x - 1) + (x - 1) = 0;

                ⇒ (3x + 1)(x - 1) = 0;

Thus, the two zeros are;

                   ⇒ (3x + 1) = 0

                   ⇒ x = -1/3;

and,            ⇒ (x - 1) = 0;

                  ⇒ x = 1;

Therefore, x = 1 or -1/3

Since, x was the positive whole number, hence the answer will be 1.

That's all.