Stmt 1 : if we put the value of b=9 in equation 15a+7b=13, we get the value of a=-10/3
mow again puting value of a=-10/3 and b= 9 in 15a+7b we get 13 as solution.
stmt 2 : sraight forward sufficient.
so, shouldnt the answer be D?
You don't have the equation \(15a + 7b = 13\) because this is the question itself "Is \(15a + 7b = 13\) ?"
You just have the value of \(b = 9\) and you don't know anything about \(a\), which can be anything.
PhD in Applied Mathematics
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