Question

Dewi and Sheila had some money. If Dewi gave Sheila $23,she would have 3/5 as much as Sheila. If Sheila gave Dewi $42 , she would have 4/5 as much money as Dewi. How much did Dewi have?

Answer 1

Let
x----------> Dewi quantity of money 
y----------> Sheila quantity of money 

we know that

(x-23)=(3/5)*y-------> equation 1
(y-42)=(4/5)*x-------> equation 2

using a graph tool----------> to calculate the system of equations
see the attached figure

the solution is the point (92.692,116.154)
x=92.692
y=116.154
Dewi quantity of money is $92.69
Sheila quantity of money is $116.15

the answer is 
Dewi have $92.69