Question

Which of the following quadratic equation has roots 3 , 5?
A) x square- 15x+ 8=0
B) x square - 8x +15=0
C) x square + 3x +5=0
D) x square + 8x - 15=0

Answer 1

Answer:

$\huge \underline \bold \red {<u>Answer</u>}$

Option c is correct.

Answer 2

Question:-

Which of the following quadratic equation has roots 3 , 5?

A) x square- 15x+ 8=0

B) x square - 8x +15=0

C) x square + 3x +5=0

D) x square + 8x - 15=0

Solution:-

1} x² - 15x + 8 = 0

put x = 3 ,

3² - 15 × 3 + 8 = 0

9 - 45 + 8 = 0 ( false )

2} x² - 8x + 15 = 0

put x = 3

3² - 8 × 3 + 15 = 0

9 - 24 + 15 = 0

24 - 24 = 0 ( True )

put x = 5 , we get

5² - 8 × 5 + 15 = 0

25 - 40 + 15 = 0

40 - 40 = 0 ( true )

Therefore 3 , 5 are roots of x² - 8x + 15 = 0

Option ( B ) is correct.