Answer
$49x^2+70xy+25y^2$
Work Step by Step
$$(7x+5y)^2$$
To square a binomial, multiply it by itself:
$$(7x+5y)(7x+5y)$$
To multiply two binomials (expressions with two terms) multiply each term in the first binomial by each term in the second binomial:
$$=(7x\times 7x)+(7x\times 5y)+(5y\times 7x)+(5y\times 5y)$$ $$=49x^2+35xy+35xy+25y^2$$
Combine like terms:
$$=49x^2+70xy+25y^2$$
