— 4х + 7y = 20 у = 3х + 15

Mathematics

1 answer:

Angelina_Jolie [31]3 years ago

6 0

Answer:

x=-5

Step-by-step explanation:

$-4x+7(3x+15)=20\\ -4x+21x+105=20\\ 17x+105=20\\ 17x=20-105\\ 17x=-85\\ x=-5$

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