Question

If A+B =7 and ab = 10.Then what is (a)Sq + (b) sq​

Answer 1

Answer:

29.

Step-by-step explanation:

Given:

a + b = 7-- equation (1)

ab = 10

We know that,

(a - b)² = (a + b)² - 4ab

(a - b)² = (7)² - 4(10)

= 49 - 40

(a - b)² = 9.

a - b = √9

a - b = ±3 equation (2)

Add both equations,

a + b + a - b = 7+3

2a = 10

a = 10/2

a = 2

Substitute "a" value in equation (1).

a + b = 7

2 + b = 7

b = 7-2

b = 5

Hence, a² + b² = (2)² + (5)²

= 4+25

a² + b² = 29

Answer 2

Answer:

A+B =7

ab=7

a^3+b^3 = ?

a^2+b^2 = (a+b)^2

(a+b)^2 = a^2+b^2+2ab

(7)^2 = a^2+b^2+2(10)

49 = a^2+b^2+20

49 -20 = a^2+b^2

a^2+b^2 = 29