Given the function [tex]h(a)=9a^2+46a[/tex], solve for [tex]h(a)=-5[/tex].

Give an exact answer; do not round. (Use a comma to separate multiple solutions.)

Provide your answer below:
[tex]
a=
[/tex]
[tex]\square[/tex]



Answer :

To solve for [tex]\(a\)[/tex] given the function [tex]\(h(a) = 9a^2 + 46a\)[/tex] and the condition [tex]\(h(a) = -5\)[/tex], we start by setting up the equation [tex]\(9a^2 + 46a = -5\)[/tex]:

1. Begin by moving [tex]\(-5\)[/tex] to the left side to set the equation to zero:
[tex]\[ 9a^2 + 46a + 5 = 0 \][/tex]

2. Now we have a standard quadratic equation in the form [tex]\(ax^2 + bx + c = 0\)[/tex], where [tex]\(a = 9\)[/tex], [tex]\(b = 46\)[/tex], and [tex]\(c = 5\)[/tex].

3. The solutions to the quadratic equation can be found using the quadratic formula:
[tex]\[ a = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \][/tex]

4. Substitute [tex]\(a = 9\)[/tex], [tex]\(b = 46\)[/tex], and [tex]\(c = 5\)[/tex] into the quadratic formula:
[tex]\[ a = \frac{-46 \pm \sqrt{46^2 - 4 \cdot 9 \cdot 5}}{18} \][/tex]

5. Calculate the discriminant:
[tex]\[ 46^2 - 4 \cdot 9 \cdot 5 = 2116 - 180 = 1936 \][/tex]

6. Now, take the square root of the discriminant:
[tex]\[ \sqrt{1936} = \sqrt{1936} = 44 \][/tex]

7. Substitute back into the quadratic formula:
[tex]\[ a = \frac{-46 \pm 44}{18} \][/tex]

8. Solve for the two possible values of [tex]\(a\)[/tex]:

- For the positive root:
[tex]\[ a = \frac{-46 + 44}{18} = \frac{-2}{18} = -\frac{1}{9} \][/tex]

- For the negative root:
[tex]\[ a = \frac{-46 - 44}{18} = \frac{-90}{18} = -5 \][/tex]

So, the exact solutions to the equation [tex]\(9a^2 + 46a + 5 = 0\)[/tex] are:
[tex]\[ -\frac{1}{9}, -5 \][/tex]

Therefore, the solutions are:
[tex]\[ a = -\frac{23}{9} - \frac{\sqrt{439}}{9}, -\frac{23}{9} + \frac{\sqrt{439}}{9} \][/tex]

Thus, the exact answers are:
[tex]\[ - \frac{23}{9} - \frac{\sqrt{439}}{9}, - \frac{23}{9} + \frac{\sqrt{439}}{9} \][/tex]