Question

Resolva os sistemas de equaçoes:

d)5x-y=7
2x+y=7

e)-3x+15y=0
20x-15y=340

URGEENTEEE

Answer 1

d)
5x-y=7
2x+y=7
some as equações
7x =14
x = 14/7
x = 2

se x = 2  calcule y
2x+y=7
2(2)+y=7
4+y=7
y = 7-4
y = 3


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e)
-3x+15y=0
20x-15y=340

17x = 340
x = 340/17
x = 20
-3x+15y=0
-3(20)+15y=0
-60+15y = 0
15y = 60
y = 60/15
y = 4

bons estudos