Multiply. \[ (5 x+4)(x+5) \]

Step 1 ：First, we multiply the first terms in each binomial: \(5x * x = 5x^2\)

Step 2 ：Next, we multiply the outer terms: \(5x * 5 = 25x\)

Step 3 ：Then, we multiply the inner terms: \(4 * x = 4x\)

Step 4 ：Finally, we multiply the last terms: \(4 * 5 = 20\)

Step 5 ：Now, we add all these results together: \(5x^2 + 25x + 4x + 20 = 5x^2 + 29x + 20\)

Step 6 ：So, \(\boxed{(5x+4)(x+5) = 5x^2 + 29x + 20}\)