Question

2. If four times a whole number is subtracted from
three times the square of the number, the result 15
is obtained. Find the number.
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Answer 1

3x² - 4x = 15

3x² - 4x - 15 = 0

3x² - 9x + 5x - 15 = 0

3x(x - 3) + 5(x - 3) = 0

(3x + 5)(x - 3) = 0

x = 3 (or) x = -5/3

HOPE IT HELPS..

Answer 2

$\bf\underline{\underline{ANSWER:}}$

Let the whole number be 'x'.

Given,

Four times a whole number is subtracted from

three times the square of the number

$\Longrightarrow$ 3x² - 4x

The result obtained is 15.

$\Longrightarrow$ 3x² - 4x = 15

$\longrightarrow$ 3x² - 4x - 15 = 0

$\longrightarrow$ 3x² - 9x + 5x - 15 = 0

$\longrightarrow$ 3x(x - 3) + 5(x - 3) = 0

$\longrightarrow$ (3x + 5)(x - 3) = 0

From the equation,

(3x + 5) = 0 $\Longrightarrow$$\boxed{x = -5/3}$

(x - 3) = 0$\Longrightarrow$ $\boxed{x = 3}$