Evaluate the expression when x - 2 and y - -4. (Enter an exact number. x2 - 9xy Need Help? Read It 4. [-/1 Points] DETAILS AUFMODMATH1 5.1A.001.PE. 0/12 Su Evaluate the variable expression when a = 5 and b = 3. 2a + 3b Need Help? Read It Watch It 5. [-/1 Points] DETAILS AUFMODMATH1 5.1A.002.PE. 0/12 Subm Evaluate the variable expression when a = 5, b = 5, and c = -2. bc : (2a) Need Help? Read It Watch It