(-2d² + s)(5d² - 6s)
Simplify.
(-2d² × 5d²) + (-2d² × 6s) + (s × 5d²) + (s × -6s)
Simplify.
-10d² + (-12d²s) + (5d²s) + (-6s²)
Take out the parenthesis.
-10d² - 12d²s + 5d²s - 6s²
Combine like terms.
-10d² + (-12d²s + 5d²s) - 6s²
Simplify.
-10d² - 7d²s - 6s²
~Hope I helped!~