Show the following quadratic equation by factorization method: 21… - Vidyadip

Question

Show the following quadratic equation by factorization method:
21x² - 28x + 10 = 0

✓

Answer

21x² - 28x + 10 = 0
We will apply discriminant rule,
$\text{x}=\frac{-\text{b}\pm\sqrt{\text{D}}}{2\text{a}}\ ...(\text{A})$
Where D = b² - 4ac
= (-28)² - 4.21.10
= 784 - 840
= -56
From (A)
$\text{x}=\frac{-28\pm\sqrt{-56}}{2.21}$
$=\frac{-28\pm2\sqrt{14}\text{ i}}{42}$
$\therefore\text{x}=\frac{2}{3}\pm\frac{\sqrt{14}}{21}\ \text{i}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "3 Marks Question" from Quadratic Equations→Quadratic Equations — all question types→MATHS STD 11 Science question papers→Rajasthan Board STD 11 Science question papers→Rajasthan Board question paper generator→

Similar questions

Prove that:
$4 \sin \alpha \cdot \sin \left(\alpha+\frac{\pi}{3}\right) \sin \left(\alpha+\frac{2 \pi}{3}\right)=\sin 3 \alpha$

If A = {1, 2} and B = {1, 3}, find A × B and B × A.

Calculate the mean deviation about median for the following data.

Class	0-10	10-20	20-30	30-40	40-50	50-60
frequency	6	7	15	16	4	2

Find equation of the line passing through the point (2, 2) and cutting off intercepts on the axis whose sum is 9.

Solve the following linear inequations in R:
$\frac{4\text{x}+3}{2\text{x}-5}<6$

25 + 22 + 19 + 16 + ... + x = 115

Using binomial theorem, expand: $\left(\frac{2 x}{3}-\frac{3}{2 x}\right)^6$

If the distance between the foci of a hyperbola is 16 and its eccentricity is $\sqrt{2},$ then obtain the equation of the hyperbola.

The sum of three numbers in G.P. is 14. If the first two terms are each increased by 1 and the third term decreased by 1, the resulting numbers are in A.P. Find the numbers.

The function f is defined by $\begin{equation} f(x)=\left\{\begin{array}{ll} {1-x,} & {x<0} \\ {1} & {, x=0} \\ {x+1,} & {x>0} \end{array}\right. \end{equation}$
Draw the graph of f(x).