Step-by-step explanation:
(4s + 2) × (5s² + 10s +3)
we know immediately the first and the last term of the result, because there is only one operation to build them :
20s³ and 6.
so, the first answer option is already eliminated.
let's multiply
4s×5s² + 4s×10s + 4×3s + 10s² + 20s + 6
20s³ + 40s² + 12s + 10s² + 20s + 6
20s³ + 50s² + 32s + 6
so, the last answer option is correct.
