Question

splitting the middle term r2_10r+21​

Answer 1

Answer:

r2 + 10r + 21

r2 + 7r + 3r + 21

r ( r+7 ) + 3 ( r+7 )

( r+3 ) ( r+7 )

Answer 2

EXPLANATION.

Factorizes : r² - 10r + 21.

As we know that,

Factorizes the equation into middle term splits, we get.

⇒ r² - 7r - 3r + 21 = 0.

⇒ r(r - 7) - 3(r - 7) = 0.

⇒ (r - 3)(r - 7) = 0.

⇒ r = 3   and   r = 7.

                                                                                                                     

MORE INFORMATION.

Conjugate roots.

(1) = If D < 0.

One roots = α + iβ.

Other roots = α - iβ.

(2) = If D > 0.

One roots = α + √β.

Other roots = α - √β.