Question

a-b=7 and a2 + b2=85, then find the value of a3-b3​

Answer 1

Step-by-step explanation:

I hope this may be use ful to you mark brainliest

Answer 2

Step-by-step explanation:

721

Step-by-step explanation:

a - b = 7a−b=7

{a}^{2} + {b}^{2} = {(a - b)}^{2} + 2aba2+b2=(a−b)2+2ab

85 = {(7)}^{2} + 2ab85=(7)2+2ab

85 = 49 + 2ab85=49+2ab

85 - 49 = 2ab85−49=2ab

36 = 2ab36=2ab

ab = 18ab=18

{a}^{3} - {b}^{3} = {(a - b)}^{3} + 3ab(a - b)a3−b3=(a−b)3+3ab(a−b)

= {(7)}^{3} + 3 \times 18 \times (7)=(7)3+3×18×(7)

= 343 + 378=343+378

= 721=721