You will be able to
• Use algebra to write two-column proofs.
• Use properties of equality to write geometric
proofs.
• Algebraic proof-
Justify Each Step When Solving an Equation
Solve 2(5 – 3a) – 4(a + 7) = 92.
Solve –3(a + 3) + 5(3 – a) = –50.
A. a = 12
B. a = –37
C. a = –7
D. a = 7
• Two column proof (formal proof)-
Write an Algebraic Proof
Write an Algebraic Proof
Proof:
Statements
Reasons
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Which of the following statements would complete
the proof of this conjecture?
If the formula for the area of a trapezoid is
, then the height h of the trapezoid is
given by
.
Proof:
Statements
Reasons
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4.
Geometric Properties of Equality
Property
Reflexive
Symmetric
Transitive
Segments
Angles
Write a Geometric Proof
If A B, mB = 2mC, and mC = 45, then
mA = 90. Write a two-column proof to verify this
conjecture.
Write a Geometric Proof
Proof:
Statements
Reasons
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5.
5.
Proof:
Statements
Reasons
1.
1.
2.
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3.
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5.
5.