Respuesta :

x=20 because you add 3x+10+x=90 because it is a right angle and then you solve for c

Answer:

x=20

Step-by-step explanation:

3x+10+x=90

4x+10=90

-10 -10

4x=80

4x/4= 80/4

x= 20

CHECK:

3(20) +10=70

70+20=90