6 - a =

(9a - 18)
First, simplify

to

/ Your problem should look like:
Second, multiply both sides by 3. / Your problem should look like:
Third, expand. / Your problem should look like:
Fourth, add 3a to both sides. / Your problem should look like:
Fifth, simplify 9a - 18 + 3a to 12a - 18. / Your problem should look like:
Sixth, add 18 to both sides. / Your problem should look like:
Seventh, add 18 + 18 to get 36. / Your problem should look like:
Eighth, divide both sides by 12. / Your problem should look like:
Ninth, since 3 goes into 12 to get 36, simplify

to 3. / Your problem should look like:
Tenth, switch sides. / Your problem should look like:

Answer:
a = 3 (one solution)
I wrote the steps down, hopefully you understand them and the answer is on the lower right corner.
Answer with Step-by-step explanation:
We are given that
u+ v and u-v are orthogonal
We have to prove that u and v must have the same length.
When two vector a and b are orthogonal then

By using the property

We know that



Magnitude is always positive
When power of base on both sides are equal then base will be equal
Therefore,

Hence, the length of vectors u and v must have the same length.