The cost of old computer is $ 357
Solution:
Let "x" be the cost of old computer
From given,
Cost of new computer = $ 709
Blairs new computer cost 5$ less than twice the cost of her old computer
Therefore,
Cost of new computer = twice the cost of old computer - 5
Cost of new computer = 2x - 5
709 = 2x - 5
2x = 709 + 5
2x = 714
Divide both sides by 2
x = 357
Thus the cost of old computer is $ 357
