Question

5. Given that a + b = 8 and ab = 15, find the value of (a+b)² and a² + b²​

Answer 1

Answer:

64 and 34

Step-by-step explanation:

Given

a + b = 8 ( square both sides )

(a + b)² = 8² = 64

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(a + b)² = 64 ← expand left side

a² + b² + 2ab = 64 ← substitute ab = 15

a² + b² + 2(15) = 64

a² + b² + 30 = 64 ( subtract 30 from both sides )

a² + b² = 34