Answer: Option C
h = 6 or h= -7
Step-by-step explanation:
We have the expression
[tex]h^2-42 = -h[/tex]
To solve add h on both sides of the equality
[tex]h^2+h-42 = -h+h[/tex]
[tex]h^2+h-42 = 0[/tex]
For an equation of the form [tex]ah^2 +bh +c[/tex] the quadratic formula is
[tex]h=\frac{-b \± \sqrt{b^2 -4ac}}{2a}[/tex]
In this case
[tex]a = 1\\b= 1\\c =-42[/tex]
[tex]h=\frac{-1 \± \sqrt{1^2 -4(1)(-42)}}{2(1)}[/tex]
[tex]h_1=6[/tex]
[tex]h_2=-7[/tex]
The answer is the option C
