RIGHT ANGLE TRIANGLES
The right angle triangle is a very important and useful
tool in sheet metal flat pattern development. Triangle rules
state that the sum of all three angles in a triangle = 180°.
If one angle = 90° then it is called a right angle
triangle.
If there is at least two known features of a right angle
triangle than the whole triangle can be solved.
TRIGONOMETRY MADE SIMPLE!
THREE IMPORTANT BUTTONS ON YOUR CALCULATOR: sin cos tan
IF A SIDE &
AN ANGLE IS KNOWN
SOLVE
FORMULAS
(E) D & B
A
tan D x B or
(B ÷ tan E)
(E) D & B
C
B ÷ cos D or
(B ÷ sin E)
(E) D & A
B
A ÷ tan D or
(A x tan E)
(E) D & A
C
A ÷ sin D or
(A ÷ cos E)
(E) D & C
A
sin D x C or
(cos E x C)
(E) D & C
B
cos D x C or
(sin E x C)
D
E
90 - D
E
D
90 - E
Do the following problems.
1. If D = 30° and C = 4.024 what is A = _________
2. If E = 60° and A = 2.012 what is C = _________
3. If D = 30° and C = 4.024 what is B = _________
4. If D = 45° and B = 2.500 what is A = _________
triangle than the whole triangle can be solved.
TRIGONOMETRY MADE SIMPLE!
THREE IMPORTANT BUTTONS ON YOUR CALCULATOR: sin cos tan
IF A SIDE &
AN ANGLE IS KNOWN
SOLVE
FORMULAS
(E) D & B
A
tan D x B or
(B ÷ tan E)
(E) D & B
C
B ÷ cos D or
(B ÷ sin E)
(E) D & A
B
A ÷ tan D or
(A x tan E)
(E) D & A
C
A ÷ sin D or
(A ÷ cos E)
(E) D & C
A
sin D x C or
(cos E x C)
(E) D & C
B
cos D x C or
(sin E x C)
D
E
90 - D
E
D
90 - E
Do the following problems.
1. If D = 30° and C = 4.024 what is A = _________
2. If E = 60° and A = 2.012 what is C = _________
3. If D = 30° and C = 4.024 what is B = _________
4. If D = 45° and B = 2.500 what is A = _________
IF YOU KNOW TWO
YOU WILL KNOW THE
WHOLE TRIANGLE!
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Sixth Edition Reformatted for Internet
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