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) + 5x² - 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
0 Comments
Your comment will be posted after it is approved.
## Leave a Reply. |
Latest Videos## Archives
May 2022
ACT is a registered trademark of ACT, Inc. SAT is a registered trademark of the College Board. ACT and SAT are not affiliated with this site. |