Question

find the value of a square + b square when a + b = 5 and ab =4​

Answer 1

Answer:

a²+b²=21.

Step-by-step explanation:

(a+b)²= a²+b²+ab

5²=a²+b²+4

25-4=a²+b²

21=a²+b².

a²+b²=21.

Answer 2

a^2+b^2 = ?

ab =4

a + b = 5

(a + b )^2 =5^2 =25 = a^2+2ab+b^2

a^2+b^2 = 25- 2×4

= 17