Chapter 5 - Quadratic Equations Exercise Ex. 5(D)

Question 1

Solve each of the following equations using the formula :

 

(i)x² - 6x =27                              (ii)x² - 10x +21=0

 

(iii)x² +6x - 10 =0                       (iv)x² +2x - 6=0

 

(v)3x²+ 2x - 1=0                         (vi)2x² + 7x +5 =0

 

(vii)               (viii) 

(ix)                     (x) 

(xi)                    (xii) 

(xiii)         (xiv)

Solution 1

 

Question 2

Solve each of the following equations for x and give, in each case, your answer correct to one decimal place :

(i)x² - 8x+5=0

(ii)5x² +10x - 3 =0

Solution 2

Question 3

Solve each of the following equations for x and give, in each case, your answer correct to two decimal places :

(i)2x² - 10x +5=0

(ii)   

(iii) 4x² – 5x – 3 = 0

(iv) x² - 3x - 9 =0

(v) x² - 5x - 10 = 0

Solution 3

(i) 

(ii) 

(iii)

 

(iv) 

(v) 

Question 4

Solve each of the following equations for x and give, in each case, your answer correct to 3 decimal places :

(i)3x² - 12x - 1 =0

(ii)x² - 16 x +6= 0

(iii)2x² + 11x + 4= 0

Solution 4

Question 5

Solve:

(i)x⁴ - 2x² - 3 =0

(ii)x⁴ - 10x² +9 =0

Solution 5

Question 6

Solve :

(i)(x² - x)² + 5(x² - x)+ 4=0

(ii)(x² - 3x)² - 16(x² - 3x) - 36 =0

Solution 6

Question 7

Solve :

(i)

(ii)

(iii)

Solution 7

Question 8

Solve the equation . Write your answer correct to two decimal places.

Solution 8

Question 9

Solve the following equation and give your answer correct to 3 significant figures:

Solution 9

Consider the given equation:

Question 10

Solve for x using the quadratic formula. Write your answer correct to two significant figures.

(x - 1)² - 3x + 4 = 0

Solution 10

Question 11

Solve the quadratic equation x² - 3(x + 3) = 0; Give your answer correct to two significant figures.

Solution 11

x² - 3(x + 3) = 0