Question

if a+b=11 and ab=30 find a^2+b^2​

Answer 1

Step-by-step explanation:

(a+b) =11

ab = 30

(a+b)² = a²+b²+2ab

(11)² = a²+b²+2×30

121 = a²+b²+60

a²+b²+60 = 121

a²+b² =121-60

a²+b² = 61.

Answer 2

Answer:

a² + b² = 61

Step-by-step explanation:

a + b = 11

a = 11 - b

ab = 30

(11 - b)*b = 30

11b - b² = 30

b² - 11b + 30 = 0

(b - 5)(b - 6) = 0

b = 5 or 6

So a = 6 or 5

So a² + b² = 6² + 5² = 36 + 25 = 61