The slope of tangent to the curve $x=t^2+3 t-8, y=2 t^2-2 t-5$ at the point (2, -1) is:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → $\frac{6}{7}$
$\frac{dx}{dt}=2t+3$, $\frac{dy}{dt}=4t-2$
$\frac{dy}{dx}=\frac{4t-2}{2t+3}$
at $x=2$
$2=t^2+3t-8$
$t^2+3t-10=0$
$t=2,-5$
so $t=2$ satisfies $y=-1$
so $\frac{dy}{dx}=\frac{4×2-2}{2×2+3}=\frac{6}{7}$