First slide

Theory of expressions

Question

If $a \in Z$ and the equation $(x - a) (x - 10) + 1 = 0$ has integral roots, then the values of $a,$ are

Moderate

A

$10, 8$
B

$12, 10$
C

$12, 8$
D

none of these

Solution

Since $a$ and $x$ are integers. Therefore,
$\begin{aligned} (x - a) (x - 10) + 1 = 0 \\ \Rightarrow (x - a) (x - 10) = - 1 \end{aligned}$
$\Rightarrow (x - a = 1$ and $x - 10 = - 1)$ or, $(x - a = - 1$ and $x - 10 = 1)$
$\Rightarrow (x = 9$ and $a = 8)$ or, $(x = 11$ and $a = 12)$
$\Rightarrow a = 8$ or, $a = 12$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App