Question
Find the value of discriminant.
x2 + 7x – 1 = 0
x2 + 7x – 1 = 0
✓
Answer
$\begin{array}{l} x ^2+7 x -1=0 \text { compare with } ax ^2+ bx + c =0 \\ \Rightarrow a =1, b =7 \text { and } c =-1 \\ \therefore b ^2-4 ac =7^2-4(1)(-1) \\ =49+4 \\ =53\end{array}$
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