Question 14 Marks
Find the value of '$m$' if the quadratic equation
$(m-12)x^{2}+2(m-12)x+2=0$ has real and equal roots.
$(m-12)x^{2}+2(m-12)x+2=0$ has real and equal roots.
Answer
View full question & answer→For equal roots, $D = 0$. $a=(m-12), b=2(m-12), c=2$.
$4(m-12)^2 - 4(m-12)(2) = 0$
$4(m-12)[(m-12) - 2] = 0$
$m-12 = 0$ (not possible for quadratic) or $m-14 = 0$.
$m = 14$.
$4(m-12)^2 - 4(m-12)(2) = 0$
$4(m-12)[(m-12) - 2] = 0$
$m-12 = 0$ (not possible for quadratic) or $m-14 = 0$.
$m = 14$.