Question

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)

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Answer 1

(a) n + 5 = 19 (n = 1)

Solution:-

LHS = n + 5

By substituting the value of n = 1

Then, LHS = n + 5

= 1 + 5

= 6

By comparing LHS and RHS :-

6 ≠ 19

LHS ≠ RHS

Hence, the value of n = 1 is not a solution to the given equation n + 5 = 19.

(b) 7n + 5 = 19 (n = – 2)

Solution:-

LHS = 7n + 5

By substituting the value of n = -2

Then, LHS = 7n + 5

= (7 × (-2)) + 5

= – 14 + 5

= – 9

By comparing LHS and RHS

-9 ≠ 19

LHS ≠ RHS

Hence, the value of n = -2 is not a solution to the given equation 7n + 5 = 19.

(c) 7n + 5 = 19 (n = 2)

Solution:-

LHS = 7n + 5

By substituting the value of n = 2

Then, LHS = 7n + 5

= (7 × (2)) + 5

= 14 + 5

= 19

By comparing LHS and RHS

19 = 19

LHS = RHS

Hence, the value of n = 2 is a solution to the given equation 7n + 5 = 19.

(d) 4p – 3 = 13 (p = 1)

Solution:-

LHS = 4p – 3

By substituting the value of p = 1

Then, LHS = 4p – 3

= (4 × 1) – 3

= 4 – 3

= 1

By comparing LHS and RHS

1 ≠ 13

LHS ≠ RHS

Hence, the value of p = 1 is not a solution to the given equation 4p – 3 = 13.

(e) 4p – 3 = 13 (p = – 4)

Solution:-

LHS = 4p – 3

By substituting the value of p = – 4

Then, LHS = 4p – 3

= (4 × (-4)) – 3

= -16 – 3

= -19

By comparing LHS and RHS

-19 ≠ 13

LHS ≠ RHS

Hence, the value of p = -4 is not a solution to the given equation 4p – 3 = 13.

(f) 4p – 3 = 13 (p = 0)

Solution:-

LHS = 4p – 3

By substituting the value of p = 0

Then, LHS = 4p – 3

= (4 × 0) – 3

= 0 – 3

= -3

By comparing LHS and RHS

– 3 ≠ 13

LHS ≠ RHS

Hence, the value of p = 0 is not a solution to the given equation 4p – 3 = 13.

Answer 2

Answer:

a) Substituting the value of n = 1

➨ n + 5 = 1 + 5 = 6

6 ≠ 19

So n = 1 is not solution for the given equation.

b) Substituting the value of n = -2

➨ 7n + 5 = 7 ( -2 ) + 5 = -14 + 5 = -9

-9 ≠ 19

So n = -2 is not solution for the given equation.

c) Substituting the value of n = 2

➨ 7n + 5 = 7 × 2 + 5 = 14 + 5 = 19

19 = 19

So, n = 2 is solution for given equation.

d) Substituting the value of p = 1

➨ 4p - 3 = 4 × 1 - 3 = 4 - 3 = 1

1 ≠ 19

So, p = 1 is not solution for given equation.

e) Substituting the value as p = -4

➨ 4p - 3 = 4 (-4) - 3 = -16 - 3 = - 19

-19 ≠ 13

So, p = -4 is not solution for given equation.

f) Substituting the value as p = 0.

➨ 4p – 3 = 4 ( 0 ) - 3 = - 3

-3 ≠ 13

So, p = -3 is not solution for equation.