Question

if a-b =9 and ab=36 evaluate (I) a+b (ii) a²-b²​

Answer 1

Answer:(i)(a + b) = 15; (ii)a²-b²​= 135

Step-by-step explanation: Given that,

a-b = 9 and ab = 36.

We know the formula; (a + b)² = (a - b)² + 4ab.

On putting given values, We get:

(a + b)² = 9² + 4×(36)

→ (a + b)² = 81 + 144

→ (a + b)² = 225

→ (a + b) = 15

Now,Given and we found that,

a - b = 9 and a + b = 15

We know the formula; a² - b² = (a + b) (a - b)

On putting given values, We get:

a² - b² = 15 × 9

→ a² - b² = 135