## College Algebra (10th Edition)

$a=-2$
We need to find $a$ so that (-1,2) is on the graph of: $f(x)=ax^{2}+4$ We plug in the point: $f(-1)=a(-1)^{2}+4$ $f(-1)=a+4$ $2=a+4$ $a=2-4$ $a=-2$