Just multiply the first term in the first parentheses by the two other terms in the second parentheses. Then do the same thing with the second term in the first parentheses.
In other words: (a + b)(c + d) = ac + ad + bc + bd
(2x + 5)(3x + 4) = (2x)(3x) + (2x)(4) + (5)(3x) + (5)(4) = 6x^2 + 8x + 15x + 20
Then combine like terms.
6x^2 + 8x + 15x + 20 = 6x^2 + 23x + 20
So, 6x^2 + 23x + 20 is the answer.