## Question

For what value of λ dose the line *y* = *x* + λ touches the ellipse

9*x*^{2} + 16*y*^{2} = 144.

### Solution

âˆµ Equation of ellipse is

Comparing this with

then we get

*a*^{2} = 16 and *b*^{2} = 9

and comparing the line *y* = *x* + λ with *y* = *mx* + *c*

If the line *y* = *x* + λ touches the ellipse

then,

.

#### SIMILAR QUESTIONS

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