Quadratic Equations Exercise 9.9 – Class X

Quadratic Equations – Exercise 9.9 – Question:

  1. Draw the graphs of the following quadratic equations:

(i) y = – x2

(ii) y = 3x2

(iii) y = 1/2 x2 – 2

(iv) y = x2 – 2x

(v) y = x2 – 8x + 7

(vi) y = (x + 2)(2 – x)

(vii) y = x2 + x – 6

(viii) y = x2 – 2x + 5

Quadratic Equations – Exercise 9.9 – Solution:

  1. Draw the graphs of the following quadratic equations:

(i) y = – x2

Solution:

x-3-2-10123
y-9-4-10-1-4-9

Quadratic Equations Exercise 9.9

 (ii) y = 3x2

Solution:

x-2-1012
y1230312

Quadratic Equations Exercise 9.9

 

 (iii) y = 1/2 x2 – 2

Solution:

x-2-1012
y03/2-23/20

Quadratic Equations Exercise 9.9

 

 (iv) y = x2 – 2x = x(x – 2)

Solution:

x-2-10123
y830-103

Quadratic Equations Exercise 9.9

 (v) y = x2 – 8x + 7

Solution:

x-10123456789
y1670-5-8-9-8-50716

Quadratic Equations Exercise 9.9
(vi) y = (x + 2)(2 – x)

Solution:

y = (x + 2)(2 – x) = 2x – x2 + 4 – 2x = -x2 + 4

Therefore, y = -x2 + 4

x-3-2-10123
y-503430-5

Quadratic Equations Exercise 9.9

 

 (vii) y = x2 + x – 6

Solution:

x-4-3-2-10123
y60-4-6-6-406

Quadratic Equations Exercise 9.9

 (viii) y = x2 – 2x + 5

Solution:

x-2-101234
y138545813

Quadratic Equations Exercise 9.9