Transcript Lesson 2.1: Writing Equations

Lesson 2.1: Writing Equations
Algebra 1 CP
Mrs. Mongold
Things to remember when writing
equations
Things to remember when writing
equations

1. Use variables to represent the
unspecified numbers or measures
(unknowns)
Things to remember when writing
equations
1. Use variables to represent the
unspecified numbers or measures
(unknowns)
 2. Turn the words into an equation

Things to remember when writing
equations
1. Use variables to represent the
unspecified numbers or measures
(unknowns)
 2. Turn the words into an equation
 3. Remember some key terms

Things to remember when writing
equations
1. Use variables to represent the unspecified
numbers or measures (unknowns)
 2. Turn the words into an equation
 3. Remember some key terms

Addition
- sum
- plus
- increased
- more than
Subtraction
-Difference
-Less than
-Fewer
-decreased
Equals
-Is
-was
4 Step Plan

4 Steps to Problem Solving
4 Step Plan

4 Steps to Problem Solving
◦ Explore the problem (read the whole thing)
4 Step Plan

4 Steps to Problem Solving
◦ Explore the problem (read the whole thing)
◦ Plan the solution (write the equation)
4 Step Plan

4 Steps to Problem Solving
◦ Explore the problem (read the whole thing)
◦ Plan the solution (write the equation)
◦ Solve the problem
4 Step Plan

4 Steps to Problem Solving
◦
◦
◦
◦
Explore the problem (read the whole thing)
Plan the solution (write the equation)
Solve the problem
Check the solution (does it make sense?)
Examples

1. Two plus the quotient of a number and
8 is the same as 16
Examples

Examples

2.Twenty-seven times k is h squared
decreased by 9
Examples

2.Twenty-seven times k is h squared
decreased by 9

27k = h2 – 9
Examples

3. Five times the number a squared is
three times the sum of b and c
Examples

3. Five times the number a squared is
three times the sum of b and c

5a2 = 3(b + c)
Examples

4.Nine times a number subtracted from
95 equals 37
Examples

4.Nine times a number subtracted from
95 equals 37

95- 9n = 37
Real-World Problem

The first ice cream plant was established in 1851, by
Jacob Fussell. Today, 2,000,000 gallons of ice cream are
produced in the United States each day. In how many
days can 40,000,000 gallons of ice cream be produced in
the United States?
Real-World Problem

The first ice cream plant was established in 1851, by
Jacob Fussell. Today, 2,000,000 gallons of ice cream are
produced in the United States each day. In how many
days can 40,000,000 gallons of ice cream be produced in
the United States?

2,000,000d = 40,000,000
Real World Problem
There are 50 members in the North Carolina Senate.
This is 70 fewer than the number in the North Carolina
House of Representatives. How many members are in
the North Carolina House of Representatives?
Real World Problem
There are 50 members in the North Carolina Senate.
This is 70 fewer than the number in the North Carolina
House of Representatives. How many members are in
the North Carolina House of Representatives?
50 = x - 70
Example Write a problem
Write your own word problem based on
the given information.
a= Rafael’s age, a+5= Tierra’s age,
a+2(a+5)=46

Translate each equation into verbal
sentences.
◦ 1. 3m+5=14
Translate each equation into verbal
sentences.
◦ 1. 3m+5=14
◦ Three times a number plus five is fourteen
Translate each equation into verbal
sentences.
◦ 2. w + v = y2
Translate each equation into verbal
sentences.
◦ 2. w + v = y2
◦ The sum of two numbers is equal to the
square of a third number
Translate each equation into verbal
sentences.
◦ 3. 13 = 2 +6t
Translate each equation into verbal
sentences.
◦ 3. 13 = 2 +6t
◦ Thirteen is equal to 2 plus the product of 6
and a number
Translate each equation into verbal
sentences.
◦ 4. ½ n + 5 = n- 7
Translate each equation into verbal
sentences.
◦ 4. ½ n + 5 = n- 7
◦ One-half a number plus five is equal to that
same number minus seven
How to use a formula
How to use a formula
◦ 1. Write the formula
How to use a formula
◦ 1. Write the formula
◦ 2. Substitute for any known variables
How to use a formula
◦ 1. Write the formula
◦ 2. Substitute for any known variables
◦ 3. Solve the equation
How to use a formula
◦
◦
◦
◦
1. Write the formula
2. Substitute for any known variables
3. Solve the equation
4. Check the answer (does it make sense?)
Important Formulas
Perimeter=2l+2w
 Area of a Square= lw or s2
 Area of a Triangle= ½ bh
 Area of a Circle= πr2
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Homework

Chapter 2 Packets pgs 7 and 8 Evens