Question

What is the area of a rectanlge with the vertices (4,6), (0,3), (3,-1) and (7,2)?

a)10
b) 15
c) 20
d) 25

Answer 1

Apply determinant

Answer 2

I dont understand determinant

Answer 3

use the distance formula

Answer 4

the distance formula will give you the lengths of the sides. luckily, you only have to do that twice, not 4 times, because rectangles have congruent opposite sides

Answer 5

i got 10, both we're 5 & 5

Answer 6

\[\frac{ 1 }{ 2 }|\left[\begin{matrix}4 & 6 \\ 0 & 3\end{matrix}\right]+\left[\begin{matrix}0 & 3 \\ 3 & -1\end{matrix}\right]+\left[\begin{matrix}3 & -1 \\ 7 & 2\end{matrix}\right]\left[\begin{matrix}7 & 2 \\ 4 & 6\end{matrix}\right]|=25\]

Answer 7

so 5 x 5 = 25

Answer 8

and that's our area