Matematika

Pertanyaan

tolong dijawab no. 1-10!!please kasih tau cara penyelesaiannya!
tolong dijawab no. 1-10!!please kasih tau cara penyelesaiannya!

1 Jawaban

  • 2) ( B )
    30 + 6x = 12
    6x = 12 - 30
    6x = -18 (bagi kedua sisi dengan 6)
    x = -3 ( B )

    3) ( C )

    -2x = 6 (bagi kedua sisi dengan -2)
    x = -3

    a) x = -3
    b)
    2x + 6 = 0
    2x = -6
    x = -3
    c)
    4x = 12
    x = 3 ( tidak ekuivalen )
    [tex]d) \frac{2}{3} x = - 2 \\ x = - 3[/tex]

    Jadi, jawabannya adalah C

    4) ( C )
    4x + 18 = 6 - 2x
    4x + 2x = 6 - 18
    6x = -12
    x = -2 ( C )

    5)
    4(2y - 3) = 4y + 10
    8y - 12 = 4y + 10
    8y - 4y = 10 + 12
    4y = 22
    [tex]y = \frac{22}{4} \\ y = \frac{11}{2} \\ y = 5 \frac{1}{2} [/tex]
    Jawabannya ( A )

    6) ( C )
    4(2y + 3) - 2y = 3(4y + 3)
    8y + 12 - 2 y = 12y + 9
    6y + 12 = 12y + 9
    6y - 12y = 9 - 12
    -6y = -3
    [tex]y = \frac{ - 3}{ - 6} \\ y = \frac{1}{2} \\ \\ y + 5 \\ = \frac{1}{2} + \frac{5}{1} \\ = \frac{1 + 10}{2} \\ = \frac{11}{2} \\ = 5 \frac{1}{2} [/tex]

    Jadi, jawabannya ( C )



    7) ( D )
    3(2x - 5) + 2(4x + 7) = 5(3x + 1)
    6x - 15 + 8x + 14 = 15x + 5
    14x - 1 = 15x + 5
    14x - 15x = 5 + 1
    -x = 6
    x = -6 ( D )

    8) ( D )
    [tex] \frac{2}{3} (2y - 3) = \frac{1}{2} (4y + 2) \\ \frac{4}{3} y - 2 = \frac{1}{2} \times 2(2y + 1) \\ \frac{4}{3} y - 2 = 2y + 1 \\ 4y - 6 = 6y + 3 \\ 4y - 6y = 3 + 6 \\ - 2y = 9 \\ y = - \frac{ 9}{2} \\ y = - 4 \frac{1}{2} [/tex]


    9) ( B )
    [tex] \frac{2y - 5}{4} + \frac{7}{12} = \frac{4y - 1}{3} \\ 3(2y + 5) + 7 = 4(4y - 1) \\ 6y - 15 + 7 = 16y - 4 \\ 6y - 8 = 16y - 4 \\ 6y - 16y = - 4 + 8 \\ - 10y = 4 \\ y = - \frac{4}{ 10} \\ y = - \frac{2}{5} [/tex]


    10) ( D )
    [tex](6x - 4)(x + 2) = 3x(2x + 4) \\ 6 {x}^{2} + 12x - 4x - 8 = 6 {x}^{2} + 12x \\ - 4x - 8 = 0 \\ - 4x = 8 \\ x = - 2 \\ \\x = p \\ \\ 2p - 3 \\ = 2( - 2) - 3 \\ = - 4 - 3 \\ = - 7[/tex]