Answer: t=20°
Step-by-step explanation:
1. By definition, the sum of the interior angles is 180 degrees.
2. Keeping the information above on mind, you can write the following expression:
[tex]90+50+2t=180[/tex]
3. Now, you must solve for [tex]t[/tex] as following:
[tex]140+2t=180\\2t=180-140\\2t=40\\t=\frac{40}{2}\\t=20[/tex]
4. Therefore, the value of [tex]t[/tex] is 20°