Question

if x+3y=5 find the value of x³+27y³+45xy​

Answer 1

${(x + 3y)}^{3} = {5}^{3}$

==>.

${x}^{3} + {3y}^{3} + 3(x)(3y) \times (x + 3y)$

$= > {x}^{3} + 27 {y}^{3} + 45xy = 125$

Simply cube on both the sides

hope you understand

Answer 2

Step-by-step explanation:

x+3y=5

(x+3y)³=5³

x³ + 27y³ + 9x²y + 27xy² = 125

x³+ 27y³ +9xy( x+ 3y) = 125

x³+27y³+ 9xy ×5 = 125 (x+3y=5)

x³ + 27y³ + 45xy = 125