update based on user feedback

clarity on evalation on metric alerts.

Author: rboucher

articles/azure-monitor/platform/alerts-metric-overview.md

@@ -34,6 +34,8 @@ Let's say you have created a simple static threshold metric alert rule as follow
 
 From the time the alert rule is created, the monitor runs every 1 min and looks at metric values for the last 5 minutes and checks if the average of those values exceeds 70. If the condition is met that is, the average Percentage CPU for the last 5 minutes exceeds 70, the alert rule fires an activated notification. If you have configured an email or a web hook action in the action group associated with the alert rule, you will receive an activated notification on both.
 
+When you are using multiple conditions in one rule, the rule "ands" the conditions together.  That is, the alert fires when all the conditions in the alert evaluate as true and resolve when one of the conditions is no longer true. And example of this type of alert would be alert when "CPU higher than 90%" and "queue length is over 300 items". 
+
 ### Alert rule with dynamic condition type
 
 Let's say you have created a simple Dynamic Thresholds metric alert rule as follows: