Will give a brainliest if ur answer is 100% !

given the literal equation ab/a+b=c, with b = –1 + a, what is the value of c if a = 5?

a.
20/9
b.
25/9
c.
4
d.
11

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?

What is the solution to the equation e3x=12? round your answer to the nearest hundredth

Asquare and an equilateral triangle have the same perimeter. each side the triangle is 4 inches longer than each side of the square. what is the perimeter of the square