Use an equation to find the value of k so that the line passing through (−4,k) and (6,−7) has a slope of −15.

k = 143

Step-by-step explanation:

Using the slope formula

(k- -7)/(-4-6) =-15

(k+7)/(-10) = -15

k+7 =-15*-10

k+7 = 150

Subtract 7

k+7-7 = 150-7

k = 143

< 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⭐