Question

if x+y=7, x²+y² is 25 then x³+y³is​

Answer 1

Answer:

x³+y³ = 91

Step-by-step explanation:

Given,

x+y=7- (1)

x²+y²=25 - (2)

Squaring on both sides equation (1)

(x+y)² = (7)²

x²+y²+2xy = 49

Substitute equation (2)

25+2xy = 49

2xy = 49-25

2xy =24

xy = 24/2

xy = 12 - (3)

Required x³+y³

(x+y)³= x³+y³+3xy(x+y)

Substitute equation (1) and (3)

(7)³ = x³+y³+3(12)(7)

343 = x³+y³+252

x³+y³ = 343-252

x³+y³ = 91

Answer 2

FINAL ANSWER:-

91

TO FIND:-

x³+y³

GIVEN:-

x+y=7

x²+y²=25

SOLUTION:-

whole solution is in the pic that i have attached