Question

In the equation below, what value can be plugged in for (a) to give it infinite solutions for 21 + 14 - 7(3x+a)

Answer 1

Answer: 21x+%2B+14+=+7%283x+%2B+a%29

21x%2B14=21x%2B7a

21x-21x%2B14=7a

14=7a

a=2