Question 737226
we know that i+j = 85 and

3i-10 = 2j+20

solve for i = 2j/3 + 10/3  

substitute in equation 1 for i

2j/3 +10/3 + j = 85

multiply both sides by 3

2j + 10 +  3j = 255

5j = 245  and j = 49 and i = 36