Question

3x2 – 48x + 153 = 0

Answer 1

Simplify it first\[
x^2 -16 x +51=0
\]

Answer 2

Use after the quadratic formula
\[\Delta=b^2-4ac=16^2 - 4(1)(51)=51\\
\sqrt \Delta = 2 \sqrt{13}
\]
The roots are
\[
x=\frac{ -b \pm 3 \sqrt{13}}{2a}
\]
Compute them.

Answer 3

A misprint in the above reply
\[
x=\frac{ -b \pm2 \sqrt{13}}{2a}
\]