Question

If x=-1 and y=3 is a solution of linear equation 3ax+4ay=9 then find the value of a for this value of a ,determine value of b from the equation (2b+1)-3(a+2)+4=0

Answer 1

3ax+4ay=9 on sub x, y values the eqn is - 3a+12a=9 so 9a=9 and a=1
(2b+1)-3(a+2)+4=0
On sub a value
(2b+1)-9+4=0
2b+1-9+4=0
2b=4
b=2

Answer 2

hey there here is your answer...
$x = - 1 \\ y = 3 \\ substituting \: in \: given \: equation \\ 3a( - 1) + 4a(3) = 9 \\ - 3a + 12a = 9 \\ 9a = 9 \\ a = 1 \\ sub...a = 1 \: in \: other \: equation$
$(2b + 1) - 3((1) + 2) + 4 = 0 \\ 2b + 1 - 9 + 4 = 0 \\ 2b = 4 \\ b = 2$
hope it helps...