Submit a question to our community and get an answer from real people.
Submit

How to find x on an isosceles triangle?

I'm given two angles, one angle is (20x-10) and another angle is (9x+4). what is x and how did you get it

Report as

(20x -10)+(20x-10)+(9x+4)=180.

Proper equation, since two of the angles must be the same. In order to get an isosceles triangle. After all the algebra.

X=4.

Helpful (1) Fun Thanks for voting Comments (1)
Report as
Thank you
Report as
Add a comment...

So by using the triangle angle sum theorem, you should know that all the angles should add up to 180 degrees. Sooo your equation would look like this:
(20x+10) + (9x+4) = 180
Subtract 10 from each side
x+9x+4 = 170
Subtract 4
20x+9x = 166
29x = 166
Divided by 29
x = about 5.724.

Then you have to plug it in to the equation to find the angles.
20(5.742) - 10 = 104. 84

9(5.742) +4 = 55.678

104.84 + 55.678 = 160.518
180 - 160.518 = 19.482
That's the last angle.

Helpful Fun Thanks for voting Comments (2)
Report as
Very wrong...
Report as
I don't even understand how you did what you just did. Your triangle only has two angles and the plus ten randomly turned into minus ten. I'm sorry but no.
Report as
Add a comment...

It depends. Are those two angles the equal ones??? If not, then which one is the base angles....cause we need to add two of those together. We need more info

Helpful Fun Thanks for voting Comments (1)
Report as
Incognito gave me the answer already, he was right
Report as
Add a comment...
Do you have an answer?
Answer this question...
Did you mean?
Login or Join the Community to answer
Popular Searches