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Example Questions 1 Ex Q1. 7y + 6 (a) y = 3 (b) y = 0 (c) y = -3 (a) = 7 x = = 27 (b) = 7 x = = 6 (c) = 7 x (-3) + 6 = = -15 (a) = x 1 = = 5 (b) = x 7 = = -13 (c) = 8 - 3(-4) = = 20 + x + = + + x - = - - x + = - - x - = + Replacing the variables in an expression with numbers is called substitution. We need to be able to substitute both positive and negative numbers within expressions that contain one or more variables. Substitution 8 - 3p (a) p = 1 (b) p = 7 (c) p = -4 Ex Q2. We will evaluate each of the expressions below for the given values. BODMAS
Questions 1 Questions + x + = + + x - = - - x + = - - x - = + Evaluate the following expressions for each given variable k + 3 (k = 7) 2. 9p + 15 (p = 3) 3. 5 x - 3 ( x = 0) 4. 7 x - 30 ( x = 2) z (z = -3) k (k = 2) 7. -6q + 2 (q = 7 ) 8. 8r - 7 (r = - ¼ ) -9 Substitution
Example Questions 2 Ex Q3. q (a) q = 4 (b) q = 0 (c) q = -5 (a) = = = 19 (b) = = = 3 (c) = (-5) = = 28 (a) = 2 x = = - 2 (b) = 2 x = = 52 (c) = 2 x (-4) = = 12 + x + = + + x - = - - x + = - - x - = + Replacing the variables in an expression with numbers is called substitution. We need to be able to substitute both positive and negative numbers within expressions that contain one or more variables. Substitution 2m (a) m = 3 (b) m = 6 (c) m = -4 Ex Q4. We will evaluate each of the expressions below for the given values. BODMAS
Questions 2 Questions + x + = + + x - = - - x + = - - x - = + Evaluate the following expressions for each given variable k (k = 3) 2. p (p = 2) 3. 5 x ( x = 3) 4. x ( x = -5) z 2 (z = -3) 6. 4k (k = 1) 7. 8q (q = -2 ) 8. 8r (r = - ½ ) -5 Substitution
Example Questions 3 Ex Q5. 3a + b (a) a = 2, b =3 (b) a = -4, b = 1 (a) = 3 x = = 9 (b) = 3 x (-4) + 1 = = -11 (a) = 4 x = = 3 (b) = - 2 x = = -4 + x + = + + x - = - - x + = - - x - = + Replacing the variables in an expression with numbers is called substitution. We need to be able to substitute both positive and negative numbers within expressions that contain one or more variables. Substitution pq - v (a) p = 4, q = 2, v = 5 (b) p = -2, q = 3, v = -2 Ex Q6. We will evaluate each of the expressions below for the given values. BODMAS
Example Questions 4 Ex Q7. 3e + 2f (a) e = 6, f = 2 (b) e = -3, f = -1 (a) = 3 x x 2 = = 22 (b) = 3 x (-3) + 2 x (-1) = = -11 (a) = 2 x 1 x x (-3 ) = = 13 (b) = 2 x (-3) x (-2) - 3 x (-5) = = 27 + x + = + + x - = - - x + = - - x - = + Replacing the variables in an expression with numbers is called substitution. We need to be able to substitute both positive and negative numbers within expressions that contain one or more variables. Substitution 2mn - 3q (a) m = 1, n = 2, q = -3 (b) m = -3, n = -2, q = -5 Ex Q8. We will evaluate each of the expressions below for the given values. BODMAS
Questions 3 + x + = + + x - = - - x + = - - x - = + Evaluate the following expressions for each given variable ab + c (a = 3, b = 2, c = 8) Substitution 5. 3pq + v (p = 2, q = 5, v = -4) BODMAS st + 3v (s = -4, t = 2, v = 6) a + b (a = 3, b = 9) 2. 3p - q (p = 2, q = 8,) 3. 5s + 2t (s = -4, t = -2,) pqr - v (p = -3, q = -2, r = 4, v = -3) 51
Worksheet worksheet 4. 2ab + c (a = 3, b = 2, c = 8) 5. 3pq + v (p = 2, q = 5, v = -4) 6. 5st + 3v (s = -4, t = 2, v = 6) 1. 2a + b (a = 3, b = 9) 2. 3p - q (p = 2, q = 8,) 3. 5s + 2t (s = -4, t = -2,) 7. 2pqr - v (p = -3, q = -2, r = 4, v = -3) 1. 4k + 3 (k = 7) 2. 9p + 15 (p = 3) 3. 5 x - 3 ( x = 0) 4. 7 x - 30 ( x = 2) z (z = -3) k (k = 2) 7. -6q + 2 (q = 7 ) 8. 8r - 7 (r = - ¼ ) 1. 2k (k = 3) 2. p (p = 2) 3. 5 x ( x = 3) 4. x ( x = -5) z 2 (z = -3) 6. 4k (k = 1) 7. 8q (q = -2 ) 8. 8r (r = - ½ ) Questions 1Questions 2Questions 3