By elimination
1. −2x + 12y = −30, x − 12y = 15 → (15, 0)2. 5x + 2y = −12, 8x − 2y = 38 → (2, −11)3. 8x + 8y = −56, −5x − 8y = 20 → (−12, 5)4. 6x + 9y = 36, 4x − 9y = −36 → (0, 4)5. −5x + 8y = −60, 6x − 8y = 56 → (−4, −10)6. x + 2y = 6, 11x − 2y = 18 → (2, 2)7. 6x + 6y = 42, 2x − 6y = −34 → (1, 6)8. −3x + 2y = 4, 7x − 2y = 12 → (4, 8)By substitution
1. y = −x + 8, 5x − 2y = −37 → (−3, 11)2. y = 2x + 13, −6x + 7y = −5 → (−12, −11)3. y = 3x − 18, −x + 9y = −6 → (6, 0)4. y = x − 7, 2x + 2y = 34 → (12, 5)5. y = 3x − 18, −12x + 7y = −36 → (10, 12)6. y = 3x + 1, 10x − 2y = −2 → (0, 1)7. y = 4x + 8, −12x + 3y = 24 → (1, 12)8. y = x + 15, 6x + 2y = 30 → (0, 15)|x + b| = c
1. |x − 4| = 6 → x = −2 or x = 102. |x − 6| = 4 → x = 2 or x = 103. |x + 4| = 4 → x = −8 or x = 04. |x − 6| = 8 → x = −2 or x = 145. |x − 1| = 6 → x = −5 or x = 76. |x + 3| = 4 → x = −7 or x = 17. |x| = 7 → x = −7 or x = 78. |x + 1| = 4 → x = −5 or x = 3|ax + b| = c
1. |3x − 6| = 6 → x = 0 or x = 42. |3x − 3| = 21 → x = −6 or x = 83. |2x − 8| = 2 → x = 3 or x = 54. |3x − 6| = 9 → x = −1 or x = 55. |2x − 4| = 4 → x = 0 or x = 46. |2x + 2| = 2 → x = −2 or x = 07. |3x − 9| = 12 → x = −1 or x = 78. |2x + 4| = 6 → x = −5 or x = 1Multiplying in scientific notation
1. (5 × 10⁻¹) × (8 × 10⁻³) = 4 × 10⁻³2. (6 × 10⁶) × (8 × 10⁻⁵) = 4.8 × 10²3. (4 × 10⁶) × (2 × 10⁵) = 8 × 10¹¹4. (3 × 10⁷) × (6 × 10²) = 1.8 × 10¹⁰5. (3 × 10⁻⁴) × (1.5 × 10⁸) = 4.5 × 10⁴6. (5 × 10⁴) × (8 × 10⁻⁴) = 4 × 10¹7. (3 × 10⁻²) × (1.5 × 10⁷) = 4.5 × 10⁵8. (2 × 10⁻¹) × (2 × 10³) = 4 × 10²Dividing in scientific notation
1. (7.5 × 10⁷) ÷ (3 × 10⁻²) = 2.5 × 10⁹2. (2 × 10³) ÷ (2.5 × 10⁸) = 8 × 10⁻⁶3. (3 × 10⁻⁴) ÷ (1.5 × 10⁸) = 2 × 10⁻¹²4. (6 × 10⁴) ÷ (3 × 10²) = 2 × 10²5. (4.5 × 10⁷) ÷ (7.5 × 10⁻³) = 6 × 10⁹6. (6 × 10⁸) ÷ (4 × 10⁴) = 1.5 × 10⁴7. (1.2 × 10³) ÷ (1.5 × 10⁵) = 8 × 10⁻³8. (4.5 × 10⁴) ÷ (7.5 × 10⁷) = 6 × 10⁻⁴