Translating Words into Symbols Objective – To translate phrases into variable expressions Words that mean addition: Sum, increased by, more than, added to, plus, total Words that mean subtraction: difference, decreased by, less than, minus Words that mean multiplication: product, times, of, twice Words that mean division: quotient, divided by, into

Translate each phrase into a variable expression 3 less than half of x ½x - 3 Be careful with phrases involving subtraction. “5 less than x” is translated as ‘x – 5’, not ‘5 – x’ Half the difference between x and 3 ½(x – 3)

The length of a board in centimeters is l. What is the length of a board that is 7 cm less? l - 7 What is the length of a board 6 cm longer? l + 6

Formulas are used a lot in Algebra. Formulas are equations that state rules about relationships. A = lwArea of a rectangle P = 2l + 2w Perimeter of a rectangle D = rtDistance formula – rate times time C = npCost - # of items times price per item

Find the area and perimeter of a rectangle with length 10 and width w A = lw = 10 · w = 10w P = 2l + 2w = (2 · 10) + (2 · w) = w

You and your friends buy 2 pizzas at p dollars each and 4 salads at s dollars each. How much did you and your friends spend? C = np Pizza cost = 2pSalad cost = 4s Total cost = 2p + 4s You spend (2p + 4s) dollars

You travel (h + ½) hours at 80 km/h. How far do you travel? D = rt = 80(h + ½) You travel 80(h + ½) hours

Assignment Page 16 –18 # 1 – 36 (Written Exercises)