`@` `10MN`

`1,` `(2x-3)^2-49=0`

`<=>(2x-3)^2-7^2=0`

`<=>(2x-3-7)(2x-3+7)=0`

`<=>(2x-10)(2x+4)=0`

`<=>` `2x-10=0` hoặc `2x+4=0`

`<=>` `x=5` hoặc `x=-2`

Vậy `x` `in{5;-2}`

`2,` `(2x-5)^2-x^2=0`

`<=>(2x-5-x)(2x-5+x)=0`

`<=>(x-5)(3x-5)=0`

`<=>` `x-5=0` hoặc `3x-5=0`

`<=>` `x=5` hoặc `x=5/3`

Vậy `x` `in{5;5/3}`

`3,` `(x+3)^2-2x=45`

`<=>x^2+6x+9-2x-45=0`

`<=>x^2+4x-36=0`

`<=>x=-2+-2sqrt{10}`

Vậy `x=-2+-2sqrt{10}`

`4,` `(5x-4)^2-49x=0`

`<=>25x^2-40x+16-49x=0`

`<=>25x^2-89x+16=0`

`<=>x=(89+-7sqrt{129})/50`

Vậy `x=(89+-7sqrt{129})/50`

`5,` `16(x-1)^2-25=0`

`<=>[4(x-1)]^2-5^2=0`

`<=>(4x-4-5)(4x-4+5)=0`

`<=>(4x-9)(4x+1)=0`

`<=>` `4x-9=0` hoặc `4x+1=0`

`<=>` `x=9/4` hoặc `x=-1/4`

Vậy `x` `in{9/4;-1/4}`