Question

plz someone help me to do this no.​

Answer 1

13

Given:

a+b = 7

ab = 12

To find:

a²- ab + b²

Solution:

a² - ab + b²

(a + b)² - 2ab - ab

(a + b)² - 3ab

(7)² - 3.12

49 - 36

13

The required answer is 13.

Answer 2

Answer:

let the two numbers be a,b

given,

sum of two numbers = 7

=>a+b=7

product of two numbers =12

=>ab=12

=>a(7-a)=12

7a-a²=12

a²-7a+12=0

a²-4a-3a+12=0

a(a-4)-3(a-4)=0

(a-3)(a-4)=0

=>a=3,4

subtitle in first equation

we get b=4,3

now, we need to find

a²-ab+b²

(3)²-3(4)+(4)²

9-12+16

=13

Hope it helps you.