Question 96936
We have , |a| = a for a > 0
    |a| = -a for a < 0

for the expression |7x -4 | = 10

for 7x -4 > 0  or x > 7/4 we have 
 7x -4 =10
 7x = 14. 
 x=2   which is > 7/4 . hence x=2 is one solution

for 7x -4 < 0 or x < 4/7 we have

-(7x - 4) =10
or -7x =6
x= -6/7 which satisfies x < 4/7

therefore -6/7 is the other solution

Hence solution set for the equation is { 2, -6/7}