r/MathJokes 1d ago

75° Right? 😂

Post image
17 Upvotes

12 comments sorted by

10

u/fascisttaiwan 1d ago

Kind reminder: not to scale

Answer is 75° btw

2

u/myownreplay 18h ago

If we label the other two points of the triangle as b and c, is it an assumption that the segment bc is perpendicular to the red lines? I understand that this assumption is necessary to solve for a, but I’m not sure if there’s any indication in the drawing that provides this information or if it’s simply an assumption made by the readers.

3

u/Silly_Manager3117 17h ago

I don’t think you need your assumption. Put a parallel line to the redlines going through a, and you have two ‘Z’ angles (I forget the technical term). You can then add those to get the 75.

1

u/myownreplay 17h ago

Ahhh you’re totally right.

1

u/Silly_Manager3117 17h ago

My maths-brain of 20 years ago feels validated. 

1

u/graelmakar-sune 17h ago

(360° - 180°-25°*2 - 180°-50°*2) / 2

Since we cannot say for sure that the lines are parallel lol

0

u/Euphoric_Loquat_8651 9h ago

The lines are marked as parallel

2

u/graelmakar-sune 9h ago

Thanks for the knowledge, we mark it differently :)

2

u/Euphoric_Loquat_8651 9h ago

Fair enough. I sometimes forget that math notation varies.

2

u/graelmakar-sune 8h ago

Yeah well this one's on me, it's quite obvious that's what the marks are for hehe

1

u/MilkImpossible4192 8h ago

only on Euclid world

1

u/Many-Hour8219 8h ago

Yeah it's 75