Chapter 2.3(a) Formulas and Problem Solving.notebook
September 06, 2016
Bellwork:
Homework Questions???
Add/Subtract
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4) Solve: 3(x ­ 5) ­ 4 = ­4(3x + 1)
5) Solve: 2x ­ (5 + x) = 4x + 7 ­ 3x Sep 3­8:01 AM
Sep 3­10:13 AM
Formula: an equation that describes a known relationship among quantities such as distance, time, volume, weight, ect.
Chapter 2.3 Formulas and Problem Solving
Solve a formula for a specified variable
Sep 3­10:13 AM
We will now solve formulas for different variables. When we solve for variables in a formula we find what the variable equals and it is not always a number.
1) Solve the distance formula for the rate:
Formula
Meaning
A = πr2
Area of a circle = pi radius squared
d = rt
Distance = rate time
V= lwh
volume rectangular prism = length width height
I = Prt
Interest = principal rate time
A = ½bh Area of a triangle = one­half base height
Sep 3­10:14 AM
Solving Equations for a Specified Variable
Step 1: Clear the equation of fractions by multiplying each side by the least common denominator
Step 2: Use the distributive property to remove grouping symbols
d = rt
Step 3: Combine like terms
2) Solve the area of a trapezoid formula for the height
A = ½(b1 + b2)h
Sep 3­10:21 AM
Step 4: Use the addition/subtraction properties to rewrite the equation
Step 5: Use division and multiplication properties to isolate the given variable
Sep 3­10:25 AM
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Chapter 2.3(a) Formulas and Problem Solving.notebook
Solve for the indicated variable:
September 06, 2016
Solve for the indicated variable:
3) Solve 2y + 5x = 10 for y
5) A = ½(b1 + b2)h for b2
4) Solve ­3x + 4y = 12 for x
6) Solve A = P + Prt for t.
Sep 3­10:28 AM
Sep 3­10:29 AM
Evan Answers
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Homework:
P. 72 #1­18 (all)
Sep 3­10:30 AM
Sep 3­10:33 AM
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