Multiple two binomials: expand and simplify (x+3)(x+4)

To expand and simplify (x+3)(x+4), we will use the distributive property:

(x+3)(x+4)
= x(x) + x(4) + 3(x) + 3(4)
= x^2 + 4x + 3x + 12
= x^2 + 7x + 12

Therefore, (x+3)(x+4) simplifies to x^2 + 7x + 12.