Question

$y=p{x}^2+12x+9$ has real roots. What is the range for the value of p?

• A. p<4
• B. p≤ 1/4
• C. p≤4
• D. p≤ 3/4

Answer 1

The correct option is C p≤4

Since the condition D $\ge$ 0 is given (as the roots are real), we will find the value of p using this condition

$D=b^2-4ac\ge 0$

${12}^2-(4\times p\times 9)\ge 0$

144-36p $\ge$ 0

144 $\ge$ 36p

p $\le$ 4