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Solve the system by substitution
-4.5x-2y=-12.5
3.25x-y=-0.75

User Dan Hook
by
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1 Answer

6 votes

Answer:

The answer to your question is: x = 1, y = 4

Explanation:

I'll change decimals to fractions

4.5 = 9/2

12.5 = 25/2

3.25 = 13/4

0.75 = 3/4

-9/2 x - 2 y = - 25/2 (I)

13/4 x - y = - 3/4 (ll)

Process

from (II) y = 13/4x + 3/4

Sunstitution -9/2x -2(13/4 x + 3/4) = - 25/2

-9/2 x - 13/2 x - 3/2 = -25/2

Multiply by 2 -9 x - 13 x - 3 = -25

-22 x = -25 + 3

-22 x = -22

x = 22/22

x = 1

y = 13/4 (1) + 3/4

y = 16/4

y = 4

User Sshow
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