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0.2x + 0.3y = 1.3.
0.4r + 0.5y = 2.3. solve by using substitution ​

User Antiqe
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1 Answer

4 votes

Answer:

x=2, y=3.

Explanation:

0.2x + 0.3y = 1.3

0.4x + 0.5y = 2.3

From the first equation y = (1.3 - 0.2x) / 0.3

Substituting in second equation:

0.4x + 0.5(1.3 - 0.2x) / 0.3 = 2.3

Multiply through by 0.3:

0.12x + 0.5(1.3 - 0.2x) = 0.69

0.12x + 0.65 - 0.1x = 0.69

0.02x = 0.04

x = 2.

Substituting for x in equation 1:

0.2* 2 + 0.3y = 1.3

0.4 + 0.3y = 1.3

0.3y = 1.3 - 0.4 = 0.9

y = 3.

Check in equation 2:

0.4 * 2 + 0.5(3) = 0.8 + 1.5 = 2.3.

- Correct.

User Ralston
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7.1k points