Answer:
Each will receive
of the cake.
Step-by-step explanation:
Let the amount of cake = c
Lisa, Juan and Isaac are the persons who are sharing half of a cake equally.
Number of persons = 3
Part of the cake shared = 
Fraction of the cake shared by each = 
=
= 
Therefore, fraction of total cake shared by each member will be
of the total amount of cake.
This is what I got I hope it can help you
We have one of those equations already solved for y, so let's sub that one into the other one and solve the equation in terms of x only:

. We will simplify that and at the same time bring the 6 over by subtraction to get a polynomial set to equal 0 that we can factor.

. We will factor that to get (x-3)(x+1) for x values of x = 3 and x = -1. a above is the choice that has the x values we need, -1 and 3.
She would answer 20 or 30 questions