Question

Help I really need the answer to this.​

Answer 1

It’s either b or c

It either of those.

Answer 2

3

Explanation:

The sides are congruent so you can write the equation (4x+9)=21.

Now you subtract 9 from 21 and you get 4x=12.

All you gotta do now is divide and you get x=3.

Hope this helps!:)