Question

To decide whether 1 is a root of quadratic equation x² + 4x – 5 = 0 or not, complete the following activity.

Activity: When x = (______)
L.H.S. = 1² + 4(______) – 5
= 1 + 4 – 5
= (______) – 5
= ______
= R.H.S
Therefore x = 1 is a root of quadratic equation x² + 4x – 5 = 0

Answer 1

When x = 1,

L.H.S. = 1² + 4(1) – 5

= 1 + 4 – 5

= 5 – 5

= 0

= R.H.S.

Therefore x = 1 is a root of quadratic equation x² + 4x – 5 = 0.