3 years ago

3x+2y=10 12x+5y=25 Solve by substitution or elimination

1 answer:

5 0

3x + 2y = 10 ....multiply by -4
12x + 5y = 25
-------------------
-12x - 8y = -40 (result of multiplying by -4)
12x + 5y = 25
------------------add
-3y = - 15
y = -15/-3
y = 5

3x + 2y = 10
3x + 2(5) = 10
3x + 10 = 10
3x = 10 - 10
3x = 0
x = 0

solution is (0,5)

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