<PRE><B>Question 29672</B>
21=4(q-6)+ 11q   ----(1)
21 = 4q-24 +11q   Adding 24 to both the sides
21+24 =4q+11q  45 = 15q
That is 15q = 45
Dividing by 15
q = 45/15 = 3
Answer: q = 3
Verification: q=3 on the RHS of (1) gives
4(q-6)+ 11q = 4X(3-6)+(11X3) = 4X(-3)+33=-12+33=21=LHS
Note: How to expand 4(q-6)
The quantity (+4) outside the bracket is multiplied with every term inside the bracket in the addition process
S0 4X(q)+4X(-6) = 4q-24
Note:(why add 24? we find -24 on the RHS, and to get rid of it we add +24  so that (-24)+24 = 0. Why should we get rid of (-24)? So that the RHS contains only the terms in the unknown q)[This is the same as bringing (-24) over to the LHS with an idea of grouping like terms and always change sign when you change side for a term)


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