Area of a triangle – Sharp EL-9900 User Manual
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Advanced Keyboard/TRIGONOMETRY USING THE SHARP EL-9900
Copyright © 2002, Sharp Electronics Corporation. Permission is granted to photocopy for educational use only.
1.
Set the calculator to operate in degrees with 2ndF SET UP B (DRG)
and 1 (Deg). Press 2ndF QUIT to exit the set up screen.
2.
Access the SOLVER by pressing 2ndF SOLVER , and press CL to delete
any equation on the screen.
3.
Type in the equation A = B•H with the keystrokes: ALPHA A ALPHA
= a/b 1 2 ALPHA
B
× ALPHA H
4.
Press 2ndF SOLVER A (METHOD) 1 (Equation) to choose the
Equation solver. Press ENTER to see the list of variables for your
equation.
5.
Find the area of a triangle with base = 4 and height = 8.35. Use
▼ to
move the blinking cursor over B and type in 4. Type in 8.35 for H
and press ENTER . Press
▲ twice to move the prompt to the A variable.
Press 2ndF EXE to find the area of 16.7.
6.
Save the formula by pressing 2ndF SOLVER
C (SAVE). Enter a name
and press ENTER .
7.
Enter A = B•C•sin
θ by pressing CL a couple times to return to and delete
the current equation. Type in the equation with the keystrokes: ALPHA A
ALPHA = a/b 1 2 ALPHA B
× ALPHA C × sin
ALPHA
θ .
8.
Consider the triangle where sides of lengths 4.8 and 5.73 enclose a 47° angle.
Press ENTER to access the variable list, enter 5.73 for B, 4.8 for C (or
vice-versa), and 47 for
θ. Move the cursor to the A variable. Press 2ndF
EXE to solve for the area.
AREA OF A TRIANGLE
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