Expand (2x-1)(x+3)
Method 1: Foil method (each term of the first bracket are multiplied by each term of the second bracket, and hence the product have 4 terms before simplifying)(2x-1)(x+3) = 2xx + 2x3 - 1x -13 =2x2 + 6x - x -3 = 2x2 + 5x - 3(* denotes multiply)Method 2: Grid method (the horizontal terms are multiplied with the vertical terms, i.e.: 2x x, -13)* 2x -1x 2x2 -x3 6x -3 Adding the 4 product terms together, we get: 2x2 - x + 6x -3 = 2x2 + 5x - 3
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