JAMB - Mathematics (1989 - No. 17)
Simplify \(\frac{324 - 4x^2}{2x + 18}\)
2(x - 9)
2(9 + x)
81 - x2
-2(x - 9)
Spiegazione
\(\frac{324 - 4x^2}{2x + 18}\) = \(\frac{18^2 - (2x)^2}{2x + 18}\)
= \(\frac{(18 - 2x)(18 + 2x)}{(2x + 18)}\)
18 - 2x = 2(9 - x)
or -2(x - 9)
= \(\frac{(18 - 2x)(18 + 2x)}{(2x + 18)}\)
18 - 2x = 2(9 - x)
or -2(x - 9)