18.5k views
3 votes
I need help with number 11

I need help with number 11-example-1
User Lvca
by
4.9k points

1 Answer

3 votes

Answer:

Explanation:

So the first thing that you'll have to recognize is that the interior angles of a triangle add to 180°

Next, note that the angle that is given as 5y -23 is also the same angle as the inside of the triangle, as well as the angle it's written on.

recognizing both of these let's you write this.

180 = 2x+13 + 47 + 5y - 23

this doesn't help us too much because there are two unknowns and only one equation. we would need two equations to solve this :(

but.....

now note, that the angle 3x and 5y - 23 are also equal. Assuming that the lines are parallel that look parallel. I think for this problem we can assume that they are.

now revise the problem

180 = 2x+13 +47 +3x

now use your algebra skillz

180 = 5x 60

180-60 = 5x

120 = 5x

120/5 = 5x/5

24 = x

now plug x into the earlier equation

180 = 2x+13 + 47 + 5y - 23

180 = 2(24) + 13 + 47 +5y - 23

180 = 48 + 13 + 47 +5y -23

180 = 109 - 23 + 5y

180 = 85 + 5y

180 - 85 = 5y

95 = 5y

19 = y

User Byoung
by
4.4k points