FormulasFormulasSWBAT use formulas to SWBAT use formulas to

solve problems solve problems

FormulasFormulas FormulasFormulas

– a rule that describes a mathematical a rule that describes a mathematical relationship involving two or more quantities. relationship involving two or more quantities.

DistanceDistance– d = r x td = r x t

Volume Volume – V = l x w x h V = l x w x h

AreaArea– A = l x w A = l x w

PerimeterPerimeter– P = 2(l + w)P = 2(l + w)

ExamplesExamples Use the distance formula to Use the distance formula to

solve. d = r x tsolve. d = r x t– A plane travels 2750 miles. If it flies at a A plane travels 2750 miles. If it flies at a

rate of 500 miles per hour, how many rate of 500 miles per hour, how many hours does the plane fly?hours does the plane fly?

– r = 55 mph, t = 5 hrs, and d = ?.r = 55 mph, t = 5 hrs, and d = ?.

ExamplesExamples

– Use the volume formula to solve. Use the volume formula to solve. V = l x w x hV = l x w x hV = 12cmV = 12cm33, l = 4m, w = 1.5m, and h=?, l = 4m, w = 1.5m, and h=?V = 75mV = 75m33, l = 5m, w = 5m, and h = ?, l = 5m, w = 5m, and h = ?

ExamplesExamples Use the perimeter formula to Use the perimeter formula to

solve. P = 2(l +w)solve. P = 2(l +w)– l = 7yds, w= 4yds, and P=?l = 7yds, w= 4yds, and P=?– P = 48 cm, w = 6 cm and l = ?.P = 48 cm, w = 6 cm and l = ?.

ExamplesExamples The perimeter of a square tile is The perimeter of a square tile is

28m. What is its area?28m. What is its area? ChallengeChallenge

– The length and width of a rectangle are The length and width of a rectangle are doubled. Write a formula of the new doubled. Write a formula of the new area. How is the area changedarea. How is the area changed

Try the problems on your paperTry the problems on your paper t = 3 hourst = 3 hours r = 65 km per hourr = 65 km per hour w = 47 ftw = 47 ft w = 9 cmw = 9 cm P = 208 ftP = 208 ft22

w = 2 mw = 2 m volume = 272 cmvolume = 272 cm33