WAEC - Further Mathematics (2021 - No. 11)
For what value of k is 4x\(^2\) - 12x + k, a perfect square?
-9
\(\frac{-9}{4}\)
\(\frac{9}{4}\)
9
설명
4x\(^2\) - 12x + k;
a = 4, b = -12, c = k.
For perfect square b\(^2\) = 4ac
(-12)\(^2\) = 4 * 4 * k;
144 = 16k
k = 144\16
k = 9