Question

use a suitable identity to solve the following
(5x+3y)²​

Answer 1

use (a+b)²= a²+b²+2ab.

Answer 2

Answer:

25x²+30xy+9y²

Step-by-step explanation:

$(a + b) {}^{2} = a { }^{2} + 2ab + b {}^{2} \\ (5x + 3y) {}^{2} = (5x) {}^{2} + 2 \times 5x \times 3y + (3y) {}^{2} \\ = 25x {}^{2} + 30xy + 9y {}^{2}$