You and your friend each start a car-washing service. you spend $25 on supplies and charge $10 per car. your friend spends $55 on supplies and charges $13 per car. how many cars do you have to wash to earn the same amount of money as your friend?

Set both equations equal to each other to solve for x ( number of cars).

10x -25 = 13x - 55

Subtract 10x from each side:

-25 = 3x-55

Add 55 to each side:

30 = 3x

Divide both sides by 3:

x = 30/3

x = 10

They will need to wash 10 cars.

< 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⭐