Question

The product of two consecutive positive odd numbers is 63. Select the correct options.

• A. One of the numbers is 5
• B. One of the numbers is 3
• C. One of the numbers is 7
• D. One of the numbers is 9

Answer 1

Answer: (C), (D)

The correct options are
C

One of the numbers is 7

D

One of the numbers is 9

Let two consecutive odd numbers be $x$ and $x+2$

$x\times x+2=63$

$x\times (x+2)=63$

$x^2+2x-63=0$

$x^2+9x-7x-63=0$

$(x+9)(x-7)=0$

$x=-9,7$

Ignoring the negative value

x = 7

x + 2 = 9

So, two numbers are 7 and 9.