If x=7, determine which lines must be parallel?

All the lines which are parallel to Y-axis including Y-axis must be parallel to the line x=7.

Explanation:

                    We can understand it by drawing the line x=7 on the graph.

In the graph, it has shown that x=7 is parallel to Y-axis.

And if we talk about a set of lines x=n, where n is a real number then these lines are parallel to y-axis.

since,  we know that if one line is parallel to another line and that line is also parallel to a third line then these three lines must be parallel.

so we can say that, All lines which are parallel to y-axis as well as y-axis are parallel to x=7.

< 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⭐

$25

step-by-step explanation:

25 - 4.50 = 20.5

20.5 / 2 = 10.25

10.25 + 10 = 20.25

20.25 - 12.50 = 7.75

therefore the answer is $25 as shown as the first number.