Answer:
B. substitute for X in first equation
First off, nicely done on the exponents. You'd be surprised on how bad some look ,:D
a)

b)
Answer:
Ellie drove 90 miles in three hours.
Step-by-step explanation:
Answer: x = 70, y = 110, z = 85
Step-by-step explanation:
If BE = CD, then using corresponding angles (are equal), x = 70
If x = 70, then 70+y = 180 (angles on a straight line)
y = 110
And z = 85 (corresponding angles again): angle ABE = angle ACD