Answer:
x=5
Step-by-step explanation:
∠D=∠E (angles opposite to equal sides are equal)
So, =3x+10
10=-3x
10=x(x-3)
we know 5×2= 10 & 5-3=2,
So, 10=5×(5-3)
10=5×2
∴x=5
the answer in the pic
hope it help
perpendicular lines