Answer: The value of x is 28.
Step-by-step explanation:
Since line m is parallel to line l.
So, we assume that
(3x+21)° and (4x-7)° are corresponding angles.
And we know that , corresponding angles formed when a transversal cut the parallel line are equal.
So, they must be equal to each other.

Hence, the value of x is 28.
Answer:
to the right of zero if postive if negative left
Answer:
5a^2 +2a
Step-by-step explanation:
Like terms are ones with the same exponent of x. They can be combined.
3a^2 +2a +2a^2
= (3a^2 +2a^2) +2a
= (3+2)a^2 +2a
= 5a^2 +2a