Answer:
x + 2 + 3x = 30
Step-by-step explanation:
Both lengths are unknown, but Ginny's car length is described in terms of Zach's car length, so we choose a variable for Zach's car length.
Let x = Zach's car length.
Zach's car length is x.
"Ginny's car is 2 more than 3 times the length of Zach's car."
Ginny's car length is 2 + 3x.
Add the lengths:
x + 2 + 3x
"The sum of the lengths of both cars is 30 inches."
x + 2 + 3x = 30
Answer: x + 2 + 3x = 30