For numbers 1 to 3, simplify the given expressions. 1. 5x+7x-2x²-10x+5 a. 3x²+3x+5 b. 3x²+2x+5 2. 7+3x-5x+6x²-2x c. 3x-3x+5 d. 2x+3x+5 a. 7-5x+3x-2x c. 7+5x+3x²-2x b. 7-5x+9x-2x d. 7+5x+9x²-2x 3 3y+4xy-6y+7y a. 3xy + 4xy²+ 7y c. 3y+4x+7y b. 7x2+7y d. x + 7y