Question

Find the values of a, b, c for following quadratic equations by comparing with standard form.

(i) x² + 2x + 1 = 0
(ii) 2x² – x + 3 = 0
(iii) x² – x – 3 = 0
(iv) x² + 5x – 4 = 0
(v) x² – 7x + 4 = 0
(vi) 4x² – 9x + 1 = 0

Answer 1

(i) Given: x² + 2x + 1 = 0
On comparing this equation with the standard form of the quadratic equation ax² + bx + c = 0, we get:
a = 1, b = 2 and c = 1

(ii) Given: 2x² – x + 3 = 0
On comparing this equation with the standard form of the quadratic equation ax² + bx + c = 0, we get:
a = 2, b = –1 and c = 3

(iii) Given: x² – x – 3 = 0
On comparing this equation with the standard form of the quadratic equation ax² + bx + c = 0, we get:
a = 1, b = –1 and c = –3

(iv) Given: x² + 5x – 4 = 0
On comparing this equation with the standard form of the quadratic equation ax² + bx + c = 0, we get:
a = 1, b = 5 and c = –4

(v) Given: x² – 7x + 4 = 0
On comparing this equation with the standard form of the quadratic equation ax² + bx + c = 0, we get:
a = 1, b = –7 and c = 4

(vi) Given: 4x² – 9x + 1 = 0
On comparing this equation with the standard form of the quadratic equation ax² + bx + c = 0, we get:
a = 4, b = –9 and c = 1