Question

9x^2 + 24x + 20 = 4

Solve this by factoring.

Thank you!

Answer 1

`\large\boxed{C.\ x=-(4)/(3)}`

Explanation:

`9x^2+24x+20=4\qquad\text{subtract 4 from both sides}\\\\9x^2+12x+12x+16=0\\\\3x(3x+4)+4(3x+4)=0\\\\(3x+4)(3x+4)=0\\\\(3x+4)^2=0\iff3x+4=0\qquad\text{subtract 4 from both sides}\\\\3x=-4\qquad\text{divide both sides by 3}\\\\x=-(4)/(3)`

Answer 2

Note that,

`9x^2+24x+20=4\Longrightarrow9x^2+24x+16`

Which factors to,

`(3x+4)^2=0\Longrightarrow3x+4=0`

And simplifies to solution C,

`\boxed{x=-(4)/(3)}`

Hope this helps.

Any additional questions please feel free to ask.

r3t40