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Hi! I just need help on substitution on this equation- 4x+25=9+2(3x + 3)

User ZheFrench
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1 Answer

4 votes

We have the equation:


4x+25=9+2\cdot(3x+3)

We can isolate x:


\begin{gathered} 4x+25=9+6x+6 \\ 4x+25=15+6x \\ 4x-6x=15-25 \\ -2x=-10 \\ x=(-10)/(-2)=5 \end{gathered}

The solution is x=5.

Now we will subtitute x=5 in the equation to check the solution is ok:


\begin{gathered} \text{The equation:} \\ 4x+25=9+2\cdot(3x+3) \\ \text{The solution x=5, so replace the value of x:} \\ 4\cdot5+25=9+2\cdot(3\cdot5+3) \\ 20+25=9+2\cdot(15+3_{}) \\ 45=9+2\cdot18 \\ 45=9+36 \\ 45=45 \end{gathered}

The solution is OK

User Nfgl
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