Learning Objective : Use and interpret formulas to answer questions about quantities and their relationship Interpret mean to find our the meaning
Work with your Partner plug in the x value to solve the rule X Rule: 2 + xAnswer
Why is it important use and interpret formulas? We use formulas in everyday life such as carpentry, medicine and especially shopping
formula- a set of symbols and variable in mathematics that expresses a rule. Example: the formula for finding the area of a rectangle is A = ℓ x ω A ℓ= 4 ω= 2
Steps to using formulas Step 1 : Read the formula Step 2: Identify the operation Step 3: Plug in the values Step 4: Solve problem using formula Yonathan bought candy and gave an equal amount to his 8 cousins. He figured out how many pieces of candy each cousin would receive by using this formula Number of pieces per cousin (X) = Total number of pieces (Y) ÷ 8 1.How many pieces of candy did each cousin get if Yonathan bought 48? 2.What if he bought 24 pieces? 3.If each cousin got 2 pieces of candy how many total pieces did Yonathan buy? X = Y ÷8 X = 48 ÷ 8 X= 6 X = Y ÷ 8 X= 24 ÷ 8 X = 3 X = Y ÷ 8 2 = Y ÷ 8 2 x 8 = 16 Y = 16
Steps to using formulas Step 1 : Read the formula Step 2: Identify the operation Step 3: Plug in the values Step 4: Solve problem using formula There are 28 students in Ms. Troy’s class. The number of boys in her class can be found using this formula Number of boys (B) = 28 – the number of girls (G) 1.If there are 20 girls, how many boys are in her class? 2.If there are 12 boys, how many girls are in her class? B = 28 - G B= 28 – 20 B = 8 B = 28- G 12= 28- G G = 28 – 12 = 16
Steps to using formulas Step 1 : Read the formula Step 2: Identify the operation Step 3: Plug in the values Step 4: Solve problem using formula Janet sold water to raise money for a trip. This is the formula she used to figure out how much money she made $3 x the number of bottles of water (W) = total money she made ($) 1.How much money did he make if he sold 5 bottles of water? 2.If Janet made $ how many bottles of water did she sale? 3 x W = $ 3 x 5 = $ $ = 15 3 x W = $ 3 x W = 30 W = 30 ÷ 3 = 10
What did we learn about today? Why is it important? Step 1 : Read the formula Step 2: Identify the operation Step 3: Plug in the values Step 4: Solve problem using formula The area of a rectangle can be found using this formula Area = Length (ℓ ) x width (ω) 1.What is the area of a rectangle that has the a length of 5cm and a width of 3cm? 2.If the Area is 21in² and the length is 3in what is the width? A = l x w A = 5cm x 3cm A = 15cm² A = l x W 21 in² = 3in x W = 21 ÷ 3= 7 in