Question

One x-intercept for a parabola is at the point (-0.4,0). Use the quadratic formula to find the other x-intercept for the parabola defined by this equation: y = 5x2 + 7x + 2 Separate the values with a comma. Round, if necessary, to the nearest hundredth.
​

Answer 1

Answer:

-1

Step-by-step explanation:

Set y=0.

$5 {x}^{2} + 7x + 2 = 0 \\ x = \frac{ - 7± \sqrt{ {7}^{2} - 4(5)(2)} }{2(5)} \\ x = \frac{ - 7± \sqrt{ 9} }{10} \\ x = \frac{ - 7±3}{10} \\ x = - \frac{2}{5} \: \: \: \: or \: \: \: \: - 1$

The x-intercepts are - 0.4 and - 1.

The other x-intercept is - 1.