The point on the curve $y=8x-x^2$, where the tangent is parallel to the line $8x-4y -1=0$ is :
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (3, 15)
Rearrange the given equation into the slope-intercept form,
$8x-4y-1=0$ $[y=mx+c]$
$⇒y=2x-\frac{1}{4}$
$⇒m=2$
$y=8x-x^2$ [Given]
$\frac{dy}{dx}=8-2x$
$⇒8-2x=2$
$⇒2x=6$
$⇒x=3$
$⇒y=8(3)-(3)^2=15$
$⇒(3,15)$