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Area of Non-Right Angled Triangles 2Area of Non-Right Angled Triangles 2
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Question 1 of 4
1. Question
Find the area of the non-right angled triangle below.Round your answer to one decimal place- (11.25) `m^2`
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Area of a Non-Right Angled Triangle
`A_triangle=1/2``b``c``sin``A`where:
`a` is the side opposite angle `A``b` is the side opposite angle `B`
`c` is the side opposite angle `C`First, label the triangle.Next, rewrite the Area formula based on the given values of the triangle.The formula needs two sides and one angle in between them (included angle).`A_triangle=1/2``b``c``sin``A`Finally, substitute the values to the revised formula and solve for the area.`b=4.2`m`c=7.1`m`A=131°``A` `=` `1/2``b``c``sin``A` `=` `1/2(``4.2``)(``7.1``)sin``131°` Substitute the values `=` `1/2(29.82)sin131°` Evaluate `sin` `131` on your calculator `=` `14.91times0.7547096` `=` `11.2527` `=` `11.25 m^2` Rounded off to two decimal places `11.25 m^2` -
Question 2 of 4
2. Question
Find the area of the non-right angled triangle below.Round your answer to two decimal places- (472.61) `cm^2`
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Incorrect
Area of a Non-Right Angled Triangle
`A_triangle=1/2``b``c``sin``A`where:
`a` is the side opposite angle `A``b` is the side opposite angle `B`
`c` is the side opposite angle `C`First, label the triangle.Next, rewrite the Area formula based on the given values of the triangle.The formula needs two sides and one angle in between them (included angle).`A_triangle=1/2``b``c``sin``A`Finally, substitute the values to the revised formula and solve for the area.`b=33`cm`c=29`cm`A=99°``A_triangle` `=` `1/2``b``c``sin``A` `=` `1/2(``33``)(``29``)sin``99°` Substitute the values `=` `1/2(957)sin99°` Evaluate `sin` `99` on your calculator `=` `478.5times0.98769` `=` `472.6088` `=` `472.61 cm^2` Rounded off to two decimal places `472.61 cm^2` -
Question 3 of 4
3. Question
Find the area of the non-right angled triangle below.Round your answer to `2` decimal places- (305.06) `cm^2`
Hint
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Incorrect
Area of a Non-Right Angled Triangle
`A_triangle=1/2``r``q``sin``P`where:
`r` is the side opposite angle `R`
`q` is the side opposite angle `Q`
`p` is the side opposite angle `P`First, label the triangle.Next, rewrite the Area formula based on the given values of the triangle.The formula needs two sides and one angle in between them (included angle).The included angle, `P`, is missing, but we can find it knowing that the sum of all interior angles in a triangle is `180°`. Subtract the other `2` known angles from `180°`.`180-(65+42)=180-107=``73°``A_triangle=1/2``r``q``sin``P`Finally, substitute the values to the revised formula and solve for the area.`r=22`cm`q=29`cm`P=73°``A_triangle` `=` `1/2``r``q``sin``P` `=` `1/2(``22``)(``29``)sin``73°` Substitute the values `=` `1/2(638)sin73°` Evaluate `sin` `73` on your calculator `=` `319times0.9563` `=` `305.06 cm^2` Rounded off to `2` decimal places `305.06 cm^2` -
Question 4 of 4
4. Question
Find the area of the non-right angled triangle below.Round your answer to `2` decimal places- (92.66) `cm^2`
Hint
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Incorrect
Area of a Non-Right Angled Triangle
`A_triangle=1/2``k``l``sin``J`where:
`j` is the side opposite angle `J``k` is the side opposite angle `K`
`l` is the side opposite angle `L`First, label the triangle.Next, rewrite the Area formula based on the given values of the triangle.The formula needs two sides and one angle in between them (included angle).The included angle, `J`, is missing, but we can find it knowing that the sum of all interior angles in a triangle is `180°`. Subtract the other `2` known angles from `180°`.`180-(38+79)=180-117=``63°``A_triangle=1/2``k``l``sin``J`Finally, substitute the values to the revised formula and solve for the area.`k=16`cm`l=13`cm`J=63°``A_triangle` `=` `1/2``k``l``sin``J` `=` `1/2(``16``)(``13``)sin``63°` Substitute the values `=` `1/2(208)sin63°` Evaluate `sin` `63` on your calculator `=` `104times0.891007` `=` `92.66 cm^2` Rounded off to `2` decimal places `92.66 cm^2`
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