Multiply these algebraic expressions
a) (x+4)(x-3)
b) (y-3)(4+6)
c) (x-5)(x-2)
a) (x+4)(x-3) = x(x) + x(-3) + 4(x) + 4(-3) = x^2 - 3x + 4x - 12 = x^2 + x - 12
b) (y-3)(4+6) = y(y) + y(6) - 3(4) - 3(6) = y^2 + 6y - 12 - 18 = y^2 + 6y - 30
c) (x-5)(x-2) = x(x) + x(-2) - 5(x) - 5(-2) = x^2 - 2x - 5x + 10 = x^2 - 7x + 10