pleaseee help!!! 3

Question

use the quadratic formula to find the roots of x^2 + 4x - 23 =0. express as exact roots and simplified which is no decimal answer. Explain how can you use your graphing  calculator that your answer is correct.

Answer 1

The quadratic equation is x² + 4x - 23 =0 .

The quadratic formula for finding the roots is  .

Now compare given quadratic equation  with general quadratic equation form ax² +bx +c = 0 .

a = 1 ,b = 4 and c = -23

x = (-4 + 10.392 )/2   and   x = (-4 - 10.392 )/2 

x = 6.392 /2 and    x = -14.392 /2

x = 3.196  and x = -7.196

Rounding the decimal values to one decimal point .

x ≈ 3.2      and  x ≈ -7.2

So the solutions for quadratic equations are x = 3.2 and -7.2 .

Now use the graphing utility to graph the quadratic equation .

So from the graph we can clearly find the zeros of a quadratic functions .

So the quadratic function have a zeros at x = 3.196 and -7.196 .