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Prove the equation (2x+5)2 = 4x (x + 5) +25

2 Answers

7 votes

Answer: x = -5/2 and x = -3/2

Explanation:

(2x + 5)2 = 4x (x + 5) +25

4x + 10 = 4x² + 20x + 25

[minus 4x on both sides.]

10 = 4x² + 16x + 25

[minus 10 on both sides.]

0 = 4x² + 16x + 15

ac = 4(15) = 60,then find the factors that add up to 16, which is 6 and 10.

0 = 4x² + 6x + 10x + 15

0 = 2x(2x + 3) + 5(2x + 3)

0 = (2x + 5)(2x + 3)

2x + 5 = 0 2x + 3 = 0

2x = -5 2x = -3

x = -5/2 x = -3/2

User PhantomSalt
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5.1k points
7 votes


\huge\text{Hey there!}


\textbf{Assuming you meant: }\mathsf{(2x + 5)^2 = 4x(x + 5) + 25}


\textbf{If so, simplify both sides of your equation you're working with}


\mathsf{ 4x^2 + 20x + 25 = 4x^2 + 20x + 25}


\textbf{SUBTRACT }\rm{\bf 4x^2}\text{ \bf to BOTH of the SIDES}


\mathsf{4x^2 + 20x + 25 - 4x^2 = 4x^2 + 20x + 25 - 4x^2}


\textbf{Simplify it!}


\mathsf{20x + 25 = 20x + 25}


\textbf{SUBTRACT 20x to BOTH of the SIDES}


\mathsf{20x + 25 - 20x = 20x + 25 - 20x}


\large\textbf{SIMPLIFY IT! (as well)}


\mathsf{25 = 25}


\textbf{SUBTRACT 25 to BOTH of the SIDES}


\mathsf{25 - 25 = 25 - 25}


\textbf{Lastly, SIMPLIFY THAT!}


\textbf{We get: }\mathsf{0 = 0}


\large\textsf{This means that your \boxed{\textsf{solutions}} are \bf REAL NUMBERS.}


\huge\textsf{Therefore, your answer should be: }\\\boxed{\mathsf{All\ \underline{\underline{REAL\ NUMBERS}}\ are\ solutions.}}}\huge\checkmark


\huge\text{Good luck on your assignment \& enjoy your day!}

~
\frak{Amphitrite1040:)}

User Spacebean
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5.3k points