Subtracting 6 from each of
5x=6=10 yields
5x=4.Dividing both sides of
5x=4 by 5 yields
x=.The value of x can now be substituted into the expression
10x+3,giving
10()+3=11 Alternatively, the expression
10+x can be rewritten as
2(5x+6)−9, and 10 can be substituted for
5x+6 giving
2(10)−9=11Choic A,B and D are incorrect. Each of these choices leads to
5x+6≠10 contradicting the given equation,
5x+6=10, For example, choice A is incorrect because if the value of
10x+3 were 4, then it would follow that x = 0.1, and the value of
5x+6 would be 6.5, not 10.