Transcript Monday, February 22nd - Mr. O`Byrne`s Website

Monday, February 22nd
Bell Ringer: A chiken burrito cost
$4.75 at Zacatacos?. You pay the
cashier with a $10.00 bill. How
much change will you get you get
back from the cashier?
HOMEWORK #8: pg. 15-31 odd
Bell Ringer Answer
Burrito Cost: $4.75
You Pay with: A $10 dollar Bill
Your Change: $5.25
Guess What?
You just solved an
equation!!!!!
Grades
Grades are Posted
Many of you are missing
last week’s test
If you are missing the test
You must come and
take it BEFORE OR
AFTER SCHOOL.
This week
Monday: I CAN solve equations using
addition and subtraction
Tuesday: I CAN solve equations using
multiplication and division
Wednesday: I CAN complete a worksheet
while Mr. O’Byrne is out
Thursday: I CAN solve two step equations
Friday: I CAN review two step equations
and take a QUIZ
Last week’s test was hard
Let’s use this week as
an opportunity to
bring the grades
BACK up!!!!
Definitions
• Equation: Mathematical sentence
ex:
x+5=10
“x plus five equals 10”
• Solution of an equation: A value that
makes the sentence true
Grocery Bags
Are these equal?
Equation Rule
Whatever is done to one
side of the equation
must be done to the
other side
Example #1 – Solve the equation
Math
Explanation
m  48  29
1. Original equation
 48
 48
m  0  77
m  77
2. Add 48 to both sides
3. -48+48=0 and 29+48=77
4. Solution
Always Check your solution
Solution: m=77
Equation: m-48=29
Substitute 77 for m
77-48=29
29=29
Example #2 – Solve the equation
Math
Explanation
142  d  97
1. Original equation
 142
 142
0  d  45
d  45
2. Subtract 142 from both
sides
3. 142-142=0 and 97-142=-45
4. Solution
Always Check your solution
Solution: d=-45
Equation: 142+d=97
Substitute -45 for d
142+(-45)=97
97=97
Example #3 – Solve the equation
After work the amount of money is Miguel’s
wallet increased by $15.75 to equal $68.
How much did he start work with?
Example #3 – Solve the equation
After work the amount of money is Miguel’s
wallet increased by $15.75 to equal $68.
How much did he start work with?
m
Example #3 – Solve the equation
After work the amount of money is Miguel’s
wallet increased by $15.75 to equal $68.
How much did he start work with?
m 15
Example #3 – Solve the equation
After work the amount of money is Miguel’s
wallet increased by $15.75 to equal $68.
How much did he start work with?
m 15 
Example #3 – Solve the equation
After work the amount of money is Miguel’s
wallet increased by $15 to equal $68.
How much did he start work with?
m  15  68
Example #3 – Solve the equation
Math
m  15.75  68
15.75 15.75
m  0  52.25
m  52.25
Explanation
1. Original equation
2. Subtract 15.75 from
both sides
3. 15.75-15.75=0 and
68-15.75=52.25
4. Solution
Always Check your solution
Solution: m=52.25
Equation: m+15.75=68
Substitute 52.25 for m
52.25+15.75=68
68=68
Example #4 – Fill in the blanks
Math
Explanation
p  36  99
?
?
p  0  135
p  ______
1. Original equation
2. _________ to both
sides
3. ______________________
4. Solution
Example #4 – Fill in the blanks
Math
Explanation
p  36  99
 36
 36
p  0  135
p  135
1. Original equation
2. Add 36 to both sides
3. -36+36=0 and 99+36=135
4. Solution
Note about the homework
These are the same thing
125  (m)  75
125  m  75
Solve and check
1. x+5=48
2. -4+b=12
3. 3.5+n=-8.5
4. A number decreases by 77 equals -18. Find
the number
5. A number increased by 16 is -21. Find the
number