BALANCING EQUATIONS

WHAT AND WHY? Today we will learn… How to use fact families to balance multiplication and division equations that include variables.

WHAT AND WHY? Today we will learn… How to use fact families to balance multiplication and division equations that include variables.

WHAT AND WHY? Today we will learn… How to use fact families to balance multiplication and division equations that include variables.

WHAT AND WHY? Today we will learn… How to use fact families to balance multiplication and division equations that include variables.

WAIT….WHAT IS AN EQUATION ?? It’s a number sentence with numbers on both sides of an equal sign. 5 x 4 = 20 or 5 x 4 = Think of it like a see-saw. If one side is too much, it won’t work. 18 ÷ 2 = 3 x 2 If it’s not even, we say that the equation is not equal like this….. 9 6

WAIT….WHAT IS AN EQUATION ?? It’s a number sentence with numbers on both sides of an equal sign. 5 x 4 = 20 or 5 x 4 = Think of it like a see-saw. If one side is too much, it won’t work. 18 ÷ 2 = 3 x 3 If both sides are equal, we can use the = sign. 9 9

YOU TRY! Is this equation = or ≠ ? 18 ÷ 6 = 3 3

YOU TRY! Is this equation = or ≠ ? 32 ≠ 9 x 4 36

YOU TRY! Is this equation = or ≠ ? 4 X 4 ≠ 54 ÷

YOU TRY! Is this equation = or ≠ ? 3 X 4 = 48 ÷ 4 12

WHAT AND WHY? Back to today’s goal… How to use fact families to balance multiplication and division equations that include variables.

WAIT….WHAT IS A VARIABLE AGAIN?? A B C D E F G … A variable is a fancy name for something that replaces a number in an equation, like a symbol or a letter. 8 x = 32 8 x = 32 8 x ? = 32 8 x M = 32 The variable chosen doesn’t make a difference in the equation. But, try not to choose O or lowercase t, l, x

WHAT AND WHY? Back to our goal… How to use fact families to balance multiplication and division equations that include variables. Because…. We don’t always know every number we need to solve a problem in real life.

MRS. SCHIFANI HAD 21 CAP ERASERS. SOME STUDENTS SHARED THEM EQUALLY. EACH STUDENT GOT 3 ERASERS. HOW MANY STUDENTS BORROWED CAP ERASERS? 21 ÷ s = 3 What is my variable in this equation? Did it matter what letter I chose? What does the variable stand for?

MRS. SCHIFANI HAD 21 CAP ERASERS. SOME STUDENTS SHARED THEM EQUALLY. EACH STUDENT GOT 3 ERASERS. HOW MANY STUDENTS BORROWED CAP ERASERS? 21 ÷ s = 3 Let’s see…for this to be balanced, I know that both sides must equal 3. And…to balance this, I know I can use my fact families! 21 ÷ 3 = s 3 x s = 21 s x 3 = 21

MRS. SCHIFANI HAD 21 CAP ERASERS. SOME STUDENTS SHARED THEM EQUALLY. EACH STUDENT GOT 3 ERASERS. HOW MANY STUDENTS BORROWED CAP ERASERS? 21 ÷ s = 3 Let’s see…for this to be balanced, I know that both sides must equal 3. And…to balance this, I know I can use my fact families! 21 ÷ 3 = s 3 x s = 21 s x 3 = 21 I remembered that: in division my biggest number is 1st

MRS. SCHIFANI HAD 21 CAP ERASERS. SOME STUDENTS SHARED THEM EQUALLY. EACH STUDENT GOT 3 ERASERS. HOW MANY STUDENTS BORROWED CAP ERASERS? 21 ÷ s = 3 Let’s see…for this to be balanced, I know that both sides must equal 3. And…to balance this, I know I can use my fact families! 21 ÷ 3 = s 3 x s = 21 s x 3 = 21 I remembered that: in division my biggest number is 1 st in multiplication my biggest number is last

MRS. SCHIFANI HAD 21 CAP ERASERS. SOME STUDENTS SHARED THEM EQUALLY. EACH STUDENT GOT 3 ERASERS. HOW MANY STUDENTS BORROWED CAP ERASERS? 21 ÷ s = 3 S = 21 ÷ 3 = s 3 x s = 21 s x 3 = 21 7

MRS. SCHIFANI HAD 21 CAP ERASERS. SOME STUDENTS SHARED THEM EQUALLY. EACH STUDENT GOT 3 ERASERS. HOW MANY STUDENTS BORROWED CAP ERASERS? 21 ÷ 7 = 3 S = 21 ÷ 3 = s 3 x s = 21 s x 3 = 21 7

Seven students have cap erasers!

HERE ARE SOME FOR YOU TO TRY…. Orange or Pink Green 27 ÷ m = 3 r ÷ 5 = m = r = 8

HERE ARE SOME FOR YOU TO TRY…. Orange or Pink Green 27 ÷ m = 3 40 ÷ r = m = 9 r = ÷ 3 = m 40 ÷ 8 = r

HERE ARE SOME FOR YOU TO TRY…. Orange or Pink Green 24 = b x = 7 x y b = y = 28

HERE ARE SOME FOR YOU TO TRY…. Orange or Pink Green 24 = b x = 7 x y b = 6 y = ÷ 4 = b 28 ÷ 7 = y

HERE ARE SOME FOR YOU TO TRY…. Orange or Pink Green r ÷ 4 = 5 f ÷ 6 = 3 x 3 r = f = 9

HERE ARE SOME FOR YOU TO TRY…. Orange or Pink Green r ÷ 4 = 5 f ÷ 6 = 3 x 3 r = 20 f = x 5 = r 9 x 6 = f

HERE ARE SOME FOR YOU TO TRY…. Orange or Pink Green r x 6 = 42 f x 9 = 6 x 6 r = f = 36

HERE ARE SOME FOR YOU TO TRY…. Orange or Pink Green r x 6 = 42 f x 9 = 6 x 6 r = 7 f = ÷ 6 = r 36 ÷ 9 = f

GOOD JOB USING FACT FAMILIES TO BALANCE EQUATIONS WITH VARIABLES! 1.If you feel orange or green: Complete the side that says “Practice” in the top right. If you feel pink: Bring your worksheet to the floor with me. 2. When you finish, keep it at your seat and work on your science study guide