You score an 86 on the first of two exams. Write and solve an equation to find the score x

Question

that you need on the second exam to have a mean score of 90.

Answer 1

i think there is a typo, so I solved for the score you need on the third exam.
90 = [2(86) + x] / 3
270 = 172 + x
98 = x
hope this helps :)