Answer:
y = [tex]-9x^2 + 54x + 63[/tex]
Step-by-step explanation:
An equation in standard form is;
[tex]y = ax^2 + bx + c[/tex]
y = -9( x + 1 ) ( x - 7 )
Distribute. multiply every term by another, and combine like terms;
y = -9 ( [tex]x^2 - 6x - 7[/tex] )
y = [tex]-9x^2 + 54x + 63[/tex]
