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 √4x-4 +√9x-9 - 2√25x - 25 +15 = 5

Answer 1

`sqrt{4x-4}+sqrt{9x-9}-2sqrt{25x-25}+15=5(x>=1)`

`<=>2\sqrt{x-1}+3sqrt{x-1}-10sqrt{x-1}+15=5`

`<=>-5sqrt{x-1}=5-15=-10`

`<=>sqrt{x-1}=2`

`<=>x-1=4<=>x=5(tm)`

Vậy `x=5`

Answer 2

Ta có: \(\sqrt{4x-4}+\sqrt{9x-9}-2\sqrt{25x-25}+15=5\)

\(\Leftrightarrow2\sqrt{x-1}+3\sqrt{x-1}-2\cdot5\sqrt{x-1}=-10\)

\(\Leftrightarrow5\sqrt{x-1}=10\)

\(\Leftrightarrow x-1=4\)

hay x=5