The cost, c, of an item (the price paid by a retailer) plus the markup, m, on that item (the retailer's profit) equals the selling price, s, of the item. the formula is upper c plus upper m equals upper s. the selling price of a computer is $1770. if the markup on the computer is $130, find the cost to the retailer for the computer.

The figure shows triangle def and line segment bc, which is parallel to ef: triangle def has a point b on side de and point c on side df. the line bc is parallel to the line ef. part a: is triangle def similar to triangle dbc? explain using what you know about triangle similarity. part b: which line segment on triangle dbc corresponds to line segment ef? explain your answer. part c: which angle on triangle dbc corresponds to angle f? explain your answer. asap