(5,2),(3,-5),(-5,-1) find the area of triangle ?

1 Answer
Apr 24, 2018

A = 32A=32 Square Units

Explanation:

Let: A(5,2)A(5,2), B(3, -5)B(3,5), C(-5, -1)C(5,1), then:

Shift CC to Origin(0, 0)(0,0), and also:

Adjust AA and BB to compensate for the shift accordingly:

C(-5+5 , -1+1) => C(0, 0)C(5+5,1+1)C(0,0)
A(5+5, 2+1) => A(10, 3)A(5+5,2+1)A(10,3)
B(3+5, -5+1) => C(8, -4)B(3+5,5+1)C(8,4)

Then we can use the following:

Area of the triangle with vertices at:

C(0, 0)C(0,0), A(x_1, y_1)A(x1,y1), and B(x_2, y_2)B(x2,y2) is:

Area = 1/2|x_1 y_2 - x_2 y_1|12|x1y2x2y1|

Therefore in this case we get:

A=1/2|(10)(-4)-(8)(3)|A=12|(10)(4)(8)(3)|

A= 1/2|-40-24|A=12|4024|

A=1/2|-64|A=12|64|

A= 1/2*64A=1264

A = 32A=32 Square Units