Question

*The sum of roots of quadratic equation x² - 9x + 18 = 0 is …….*

1️⃣ -9
2️⃣ 9
3️⃣ -18
4️⃣ 18​

Answer 1

Answer:

9

Step-by-step explanation:

in this quadratic equation

a=1, b= -9 , c = 18

the sum of roots = -b/a

= -(-9)/1 = 9

Answer 2

$\huge\bf\purple{\mid{\overline{\underline{Answer :- }}}\mid}$

Option. 2) 9

$\huge\bf\green{\mid{\overline{\underline{Solution :- }}}\mid}$

$\sf{\huge{\underline{\red{Given :-}}}}$

• An equation x² - 9x + 18 = 0 .

$\sf{\huge{\underline{\orange{To\:Find :-}}}}$

• The sum of roots of quadratic equation.

$\sf{\huge{\underline{\pink{Answer :-}}}}$

An equation,

x² - 9x + 18 = 0 .

➝ x² - 6x - 3x + 18 = 0

➝ x ( x - 6 ) -3 ( x -6 ) = 0

➝ (x - 3) (x - 6) = 0

Case 1 :-

(x - 3) = 0

➝ x = 3

Case 2 :-

(x - 6) = 0

➝ x = 6

The sum of roots = 6 + 3 = 9

Hence, The sum of roots of quadratic equation is 9 .