# solve and explain, thank you: 3x^2= x+4 ; 25= 9x^2 - 30x

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`3x^2= x+4` ;

`25= 9x^2 - 30x `

`3x^2= x+4 `

`3x^2-x-4 `

`3xx-4=-12 ` factors that add to -12 = -4 and 3

`3x^2+3x-4x-4 `

factors

`(3x^2+3x)(-4x-4) `

`3x(x+1)-4(x+1) `

`(3x-4)(x+1) `

`3x-4=0 `

`x=4/3` or `1 1/3`

x+1=0

x=1

`-25= 9x^2 - 30x `

`9x^2-30x+25 `

find the square root of a and c

`(3x+5)(3x+5) `

`x=-5/3`