1. Раскройте скобки и упростите:

a) $$-5(2x - 5) = -5 \cdot 2x - 5 \cdot (-5) = -10x + 25$$ b) $$-9 - (5x + y) = -9 - 5x - y$$ c) $$-(7x - 5) = -7x + 5$$ d) $$3 + (8x + 5y) = 3 + 8x + 5y$$