Check whether the value given in the brackets is a solution to the given equation or not:
(a) n + 5 = 19 (n = 1)
(b) 7n + 5 = 19 (n = – 2)
(c) 7n + 5 = 19 (n = 2)
(d) 4p – 3 = 13 (p = 1)
(e) 4p – 3 = 13 (p = – 4)
(f) 4p – 3 = 13 (p = 0)
(a) n + 5 = 19 (n = 1)
(b) 7n + 5 = 19 (n = – 2)
(c) 7n + 5 = 19 (n = 2)
(d) 4p – 3 = 13 (p = 1)
(e) 4p – 3 = 13 (p = – 4)
(f) 4p – 3 = 13 (p = 0)
Solution and Explanation
(a) n + 5 = 19 (n = 1) Putting n = 1 in L.H.S., n + 5 = 1 + 5 = 6 ≠ 19
As L.H.S. ≠ R.H.S.,
Therefore, n = 1 is not a solution of the given equation, n + 5 = 19.
(b) 7n + 5 = 19 (n = -2) Putting n = -2 in L.H.S., 7n + 5 = 7 x (-2) + 5 = -14 + 5 = -9 ≠ 19 As L.H.S. ≠ R.H.S., Therefore, n = -2 is not a solution of the given equation, 7n + 5 = 19.
(c) 7n + 5 = 19 (n = 2)
Putting n = 2 in L.H.S.,
7n + 5 = 7 x (2) + 5 = 14 + 5 = 19 = R.H.S. As L.H.S. = R.H.S.,
Therefore, n = 2 is a solution of the given equation, 7n + 5 = 19.
(d) 4p - 3 = 13 (p = 1)
Putting p = 1 in L.H.S.,
4p - 3 = (4 x 1) - 3 = 1 ≠ 13 As L.H.S ≠ R.H.S.,
Therefore, p = 1 is not a solution of the given equation, 4p - 3 = 13.
(e) 4p - 3 = 13 (p = -4)
Putting p = -4 in L.H.S.,
4p - 3 = 4 x (-4) - 3 = - 16 - 3 = -19 ≠ 13 As L.H.S. ≠ R.H.S.,
Therefore, p = -4 is not a solution of the given equation, 4p - 3 = 13.
(f) 4p - 3 = 13 (p = 0)
Putting p = 0 in L.H.S.,
4p - 3 = (4 x 0) - 3 = -3 ≠ 13 As L.H.S. ≠ R.H.S.,
Therefore, p = 0 is not a solution of the given equation, 4p - 3 = 13.
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