Question
$3(x + 2) - 2(x - 1) = 7$
✓
Answer
$3(x + 2) - 2(x - 1) = 7$ On expanding the brackets,
we get $3x + 3 × 2 - 2 × x + 2 × 1 = 7 3x + 6 - 2x + 2 = 7 3x - 2x + 6 + 2 = 7 x + 8 = 7$
Subtracting $8$ from both sides,
we get $x + 8 - 8 = 7 - 8 x = -1$
Verification: Substituting $x = -1$ in $L.H.S.,$
we get $L.H.S. = 3(x + 2) - 2(x - 1) = 3(-1 + 2) - 2(-1 -1) = (3 × 1) - (2 × -2) = 3 + 4 = 7$, and
$R.H.S. = 7 L.H.S. = R.H.S.$
Hence, verified.
we get $3x + 3 × 2 - 2 × x + 2 × 1 = 7 3x + 6 - 2x + 2 = 7 3x - 2x + 6 + 2 = 7 x + 8 = 7$
Subtracting $8$ from both sides,
we get $x + 8 - 8 = 7 - 8 x = -1$
Verification: Substituting $x = -1$ in $L.H.S.,$
we get $L.H.S. = 3(x + 2) - 2(x - 1) = 3(-1 + 2) - 2(-1 -1) = (3 × 1) - (2 × -2) = 3 + 4 = 7$, and
$R.H.S. = 7 L.H.S. = R.H.S.$
Hence, verified.
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