Question

If the points $(6,8),(1,0)$ lie on the parabola $x^2+Ax-By-2=0$ then the values of $A$ and $B$ are

• A. $A=1,B=5$
• B. $A=2,B=4$
• C. $A=3,B=-7$
• D. $A=-3,B=8$

Answer 1

The correct option is A $A=1,B=5$

If the points $(6,8),(1,0)$ lie on the parabola $x^2+Ax-By-2=0$
Then $6^2+A\left(6\right)-B\left(8\right)-2=0$

$\Rightarrow 3A-4B+17=0$ ........(1)
And $1^2+A\left(1\right)-B\left(0\right)-2=0$

$\Rightarrow A=1$
Thus using (1), $3-4B+17=0$

$\Rightarrow B=5$
Hence $A=1,B=5$ are the required solution.