Question
Solve the following equations. Check your result in case. $0.18(5x - 4) = 0.5x + 0.8$
✓
Answer
$0.18(5\text{x} - 4) = 0.5\text{x} + 0.8$
$\frac{18}{100}(5\text{x}-4)=\frac{5}{10}\text{x}+\frac{8}{10}$
$\frac{18(5\text{x}-4)=50\text{x}+80}{100}$
$\Rightarrow90\text{x}-72=50\text{x}+80$
$\Rightarrow90\text{x}-50\text{x}=80+72$
$\Rightarrow40\text{x}=152$
$\Rightarrow\text{x}=\frac{152}{40}=\frac{38}{10}=3.8$
$\therefore\text{x}=3.8$
Check: $L.H.S. = 0.18(5x - 4) = 0.18(5 \times 3.8 - 4)$
$= 0.18(19.0 - 4)$
$= 0.18 \times 15 = 2.70$
$= 2.7 R.H.S.$
$= 0.5x + 0.8$
$= 0.5 \times 3.8 + 0.8$
$= 1.90 + 0.8$
$= 1.9 + 0.8$
$= 2.7$
$\because L.H.S. = R.H.S.$
Hence $x = 3.8$
$\frac{18}{100}(5\text{x}-4)=\frac{5}{10}\text{x}+\frac{8}{10}$
$\frac{18(5\text{x}-4)=50\text{x}+80}{100}$
$\Rightarrow90\text{x}-72=50\text{x}+80$
$\Rightarrow90\text{x}-50\text{x}=80+72$
$\Rightarrow40\text{x}=152$
$\Rightarrow\text{x}=\frac{152}{40}=\frac{38}{10}=3.8$
$\therefore\text{x}=3.8$
Check: $L.H.S. = 0.18(5x - 4) = 0.18(5 \times 3.8 - 4)$
$= 0.18(19.0 - 4)$
$= 0.18 \times 15 = 2.70$
$= 2.7 R.H.S.$
$= 0.5x + 0.8$
$= 0.5 \times 3.8 + 0.8$
$= 1.90 + 0.8$
$= 1.9 + 0.8$
$= 2.7$
$\because L.H.S. = R.H.S.$
Hence $x = 3.8$
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