You can multiply these binomials using the FOIL method--multiply the First terms, the Outer terms, the Inner terms, then the Last terms:First terms: 4x times x = 4x^2Outer terms: 4x times 2 = 8xInner terms: -5 times x = -5xLast terms: -5 times 2 = -104x^2 + 8x - 5x - 10Then combine like terms: 8x - 5x = 3xAnd your answer is 4x^2 + 3x - 10