Solving Inequalities Inequalities are solved in the
same manner as equations. The only exception in solving inequalities is that number
you negative reverse the direction of the inequality.mustSolve:
In the next example, reverse the direction of the inequality.do notSolve:
Switching the direction of the inequality is based solely on the last step and whether or not you multiply or divide by a negative number. (i.e. Is the coefficient to the variable negative or not? If it is negative, reverse the inequality in the last step … If it is not negative, leave the inequality in its original position.) To graph an inequality, it is helpful to solve for the
variable on the left. The graphing makes much more sense that way. For example, if we solved an inequality and the
answer was It is much easier to express the answer in a graph and in interval
notation when the variable is on the left. Use a bracket when
the inequality is (graph) [ 8 (interval notation)
Graph the solution x < 5 and write in interval notation: 5 (interval notation)
Notice that the arrow to the answer would point in the direction of the inequality, assuming that the inequality is solved so that the variable is on the left (as discussed above.) S Solve:
(graph) [ ) -3 8 (interval notation)
Solve:
_{
}
(graph) ( ] -3 14 (interval notation)
The views and
opinions expressed in this page are strictly those of Mary Lou Baker. This page was edited on 09-Jan-2014 |