Question

Resolva os sistemas

9x+15y=33
20×-15y=25

Answer 1

9x+15y=33
20×-15y=25
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29x / = 58
x = 58/2
x = 2

20x - 15y = 25
20(2) - 15y = 25
40 - 15y = 25
-15y = 25 - 40
-15y = - 15(-1)
15y = 15
y = 15/15
y = 1

S = { 2, 1}

Um abraço.

Answer 2

9x + 15 y = 33
20x - 15 y = 25

29x           = 58
x = 58 : 29
x= 2


9x + 15 y = 33
9.2 + 15 y = 33
15 y = 33 - 18
15y = 15
y = 15 : 15
y = 1

S= {2,1}