Solve for x and y: 0.3x + 0.5y = 0.5, 0.5x + 0.7y = 0.74 - Vidyadip

Question

Solve for $x$ and $y:$
$0.3x + 0.5y = 0.5,$
$0.5x + 0.7y = 0.74 $

✓

Answer

The given equations are:
$0.3x + 0.5y = 0.5 ...(i)$
$0.5x + 0.7y = 0.74 ...(ii)$
Multiply $(i)$ by $5$ and $(ii)$ by $3$ and subtract $(ii)$ from $(i).$
$⇒ 2.5y - 2.1y = 2.5 - 2.22$
$⇒ 0.4y = 0.28$
$⇒ y = 0.7$
Substitute $y = 0.7$ in $(i),$ we get
$⇒ 0.3x + 0.5(0.7) = 0.5$
$⇒ x = 0.5$
So, $x = 0.5$ and $y = 0.7$

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