Respuesta :

Answer:

x=25

Step-by-step explanation:

4x-10=90

4x=100

x=25

snog

Answer:

25

Step-by-step explanation:

We know that m∠9 is 90° because the diagonals of a square are perpendicular.

4x - 10 = 90

4x = 100

x = 25°