I bought 2

I bought 2 bottle of alcohol and 2 sanitizer for Php126. How much is a bottle of alcohol, if the costs of alcohol is five times the costs of sanitizer?

Correct answer:

a =  52.5 Php

Step-by-step explanation:

$$\begin{gathered} 2a+2s=126 \\ a=5s \\ 2\cdot a+2\cdot s=126 \\ a=5\cdot s \\ 2a+2s=126 \\ a-5s=0 \\ Row2-\frac{1}{2}\cdot Row1\to Row2 \\ 2a+2s=126 \\ -6s=-63 \\ s=\frac{-63}{-6}=10.5 \\ a=\frac{126-2s}{2}=\frac{126-2\cdot 10.5}{2}=52.5=52.5\text{Php} \\ a=\frac{105}{2}=52.5 \\ s=\frac{21}{2}=10.5 \end{gathered}$$

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