To solve the quadratic equation \(84x^2 + 16x = 0\), we can factor out the common term, which is \(x\):
\[ x(84x + 16) = 0 \]
Setting each factor equal to zero gives us two possible solutions:
- \(x = 0\)
- \(84x + 16 = 0\)
Now, solving the second equation:
\[ 84x + 16 = 0 \implies 84x = -16 \implies x = -\frac{16}{84} \]
Simplifying \(-\frac{16}{84}\):
\[ -\frac{16}{84} = -\frac{4}{21} \]
Thus, the solutions to the equation \(84x^2 + 16x = 0\) are:
\[ x = 0 \quad \text{and} \quad x = -\frac{4}{21} \]
So the correct response is:
x = −4/21 and x = 0.