(2x+3)^2-3x(x+4)=25 help me pls

Expand the bracketed terms:

 

4x²+ 12x + 9 - 3x² - 12x = 25

 

Collect like terms:

 

x² + 9 = 25

 

Subtract 9 from both sides:

 

x² = 16

 

Take square root:

 

x = 4, and x = -4

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