X-2y= 15 2x + 4y = -18 OA. x= 1, y= -6 OB. x= 1, y=-7 OC. x= 3, y= -6 D. x = 3, y=-7

Question

X-2y= 15
2x + 4y = -18
OA. x= 1, y= -6
OB. x= 1, y=-7
OC. x= 3, y= -6
D. x = 3, y=-7

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Nho 4 years 2021-08-11T08:09:58+00:00 1 Answers 18 views 0

Answers ( )

  1. giabao
    0
    2021-08-11T08:11:36+00:00
    Reply

    Answer:

    Option C: x=3 and y= -6 is the correct answer.

    Step-by-step explanation:

    Given that:

    x – 2y = 15     Eqn 1

    2x+4y = -18    Eqn 2

    Multiplying Eqn 1 by 2

    2(x-2y=15)

    2x-4y=30    Eqn 3

    Adding Eqn 2 and Eqn 3,

    (2x+4y)+(2x-4y)=-18+30

    2x+4y+2x-4y=12

    4x=12

    Dividing both sides by 4

    \frac{4x}{4}=\frac{12}{4}\\x=3

    Putting x=3 in Eqn 2

    2(3)+4y=-18

    6+4y=-18

    4y= -18-6

    4y= -24

    Dividing both sides by 4

    \frac{4y}{4}=\frac{-24}{4}\\y=-6

    Hence,

    Option C: x=3 and y= -6 is the correct answer.

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Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )