What is the value of (x + 2)(x  3) + 5, when x²  x  6 =  4 ? A.) 2 B.) 1 C.) 1 D.) 2 E.) 3 Solve the equation x²  x  6 =  4, for x, and then substitute the value(s) into (x + 2)(x  3) + 5
x²  x  6 =  4 x²  x  2 = 0 {added 4 to each side} (x  2)(x + 1) = 0 {factored into two binomials} x  2 = 0 or x + 1 = 0 {set each factor equal to 0} x = 2 or x = 1 {added 2 in first equation and subtracted 1 in second equation} Beginning to get worried because you just got 2 solutions for x, and the answer choices only show 1 number?? Read on! (x + 2)(x  3) + 5 = (2 + 2)(2  3) + 5 {substituted 2 in for x} = 4(1) + 5 {worked inside parentheses} =  4 + 5 {multiplied} = 1 {added} (x + 2)(x  3) + 5 = (1 + 2)(1  3) + 5 {substituted 1 in for x} = 1(4) + 5 {worked inside parentheses} = 4 + 5 {multiplied} = 1 {added} C.) 1  Algebra House
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