Question

In a quadratic equation with leading coefficient 1, a student

reads the coefficient 16 of x wrongly as 19 and obtain the

roots as –15 and –4. The correct roots are –

• A. 6, 10
• B. –6, –10
• C. –7, –9
• D. None of these

Answer 1

Answer: (B)

–6, –10

Answer 2

Eqn (Exact) = x² + 16x + 60 = 0

⇒ Exact roots – 10, – 6

If coeff. or x is taken 19 in stead of 16 then roots are – 15 and – 4 ⇒ Product is right $\frac { \mathrm { c } } { \mathrm { a } }$ = – 15x –4 = 60