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