Question

Write the set A={x:x is a factor of 24} in the roster form.
Find the quadratic polynomial whose zeroes are 4 and -2.
Find the value of 'k' for which pair of linear equations 3x-9y+7=0
and x+ky+5=0 represent parallel lines.
Express 21168 as product of its prime factors.​

Answer 1

Answer:

1) A={1,2,3,4,6,8,12,24}

2)

${x}^{2} - 2x - 8 = 0$

3) k= -3

4)21168= 2×2×2×2×3×3×3×7×7

Step-by-step explanation:

Q1)Write the set A={x:x is a factor of 24} in the roster form.

Ans. Factors of 24 are

24 =1,2,3,4,6,8,12,24

A={1,2,3,4,6,8,12,24}

Q2)Find the quadratic polynomial whose zeroes are 4 and -2.

Ans.

$\alpha + \beta = \frac{ - b}{a} = 4 + ( - 2) = 2 \\ \\ \alpha \beta = \frac{c}{a} = 4 (- 2) = - 8$

polynomial is

${x}^{2} - 2x - 8 = 0$

Q3.Find the value of 'k' for which pair of linear equations 3x-9y+7=0

and x+ky+5=0 represent parallel lines.

Ans.

If two lines are parallel then coefficients of lines

$\frac{a1}{a2} = \frac{b1}{b2} \neq \frac{c1}{c2} \\ \\ \frac{3}{1} = \frac{ - 9}{k} \neq \frac{7}{5}$

To make these equal,k should equal to -3

k=-3

Q4.Express 21168 as product of its prime factors.

Answer:

21168= 2×2×2×2×3×3×3×7×7

Hope it helps you.