jika titk puncak f(x)=x^2-bx+7 mempunyai absis 4,maka ordinatnya adalah

Parabola

f(x) = x² - bx + 7
a = 1
b = -b
c = 7

Puncak
xp = -b/2a = 4
-(-b)/2 = 4
b = 4 × 2
b = 8

f(x) = x² - 8x + 7
yp = f(4) = 4² - 8.4 + 7
yp = 16 - 32 + 7
yp = -16 + 7
yp = -9

Ordinat puncak = yp = -9

f(x)=x^2-bx+7

Xp= -b/2a
4 = -(-b)/2(1)
8 = b

maka f(x)=x^2-8x+7

yp=D/-4a
=b^2-4ac/-4a
= 64-4(1)(7)/-4
=36/-4
=-9