Question
Solve for x and y:
0.4x + 0.3y = 1.7,
0.7x - 0.2y = 0.8
0.4x + 0.3y = 1.7,
0.7x - 0.2y = 0.8
✓
Answer
The given equations are: 0.4x + 0.3y = 1.7 ...(i) 0.7x - 0.2y = 0.8 ...(ii)Multiply (i) by 0.2 and (ii) by 0.3 add them
⇒ 0.8x + 2.1x = 3.4 + 2.4
⇒ 2.9x = 5.8
⇒ x = 2
Substitute x = 2 in (i), we get
⇒ 0.4(2) + 0.3y = 1.7
⇒ y = 3
So, x = 2 and y = 3
⇒ 0.8x + 2.1x = 3.4 + 2.4
⇒ 2.9x = 5.8
⇒ x = 2
Substitute x = 2 in (i), we get
⇒ 0.4(2) + 0.3y = 1.7
⇒ y = 3
So, x = 2 and y = 3
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