Subtract 6 from both sides: Subtract 6 from both sides of the inequality to isolate the term containing a.6+5a≤15a≤1−65a≤−5
Divide by 5: Divide both sides of the inequality by 5 to solve for a.5a≤−5a≤−5/5a≤−1
Check solution: Check the solution by substituting a=−1 back into the original inequality to ensure it makes the inequality true.6+5(−1)≤16−5≤11≤1Since 1 is equal to 1, the inequality holds true.