Solve `2sin^(2)x-5sinxcosx-8cos^2x=-2`

Explanation

`2sin^2x-5sinxcosx-8cos^2x = -2`

Dividing this equation by `cos^2x`,

`=>2tan^2x - 5tanx - 8 = -2sec^2x`

`=>2tan^2x - 5tanx - 8 = -2(1+tan^2x)`

`=>2tan^2x - 5tanx - 8 = -2-2tan^2x)`

`=>4tan^2x - 5tanx - 6 = 0`

`=>4tan^2x - 8tanx +3tanx - 6 = -0`

`=>(4tanx+3)(tanx-2) = 0`

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