1. Find the vertex of y = – x2 - 4x + 5

(- 2, 9 )

Step-by-step explanation:

Given a parabola in standard form, y = ax² + bx + c : a ≠ 0

Then the x- coordinate of the vertex is

= -

y = - x² - 4x + 5 ← is in standard form

with a = - 1 and b = - 4, thus

= - = - 2

Substitute x = - 2 into equation for corresponding y- coordinate

y = - (- 2)² - 4(- 2) + 5 = - 4 + 8 + 5 = 9

vertex = (- 2, 9 )

f

step-by-step explanation:

f

< coa = 150 ( given)

as ba and bc are tangents

so oc and oa is perpendicular to cb and ab respectively because in circle normal passes through centre

so in quadrilateral oabc

< coa + < oab + < ocb + < abc = 360

150 +90+90 + < abc = 360

330 + < abc = 360

< abc = 360 -330 = 30

so < abc = 30

⭐dhruv⭐