Can anyone help explain how to work this problem out?

One factor in flood safety along a levee is the area that will absorb water should the levee break. the coordinates that make up the boundry area are (0,0),(2.8,2.1)and(4.3,4.4) what is the area of the land that would absorb the water?

I believe its
a=]x1,y1,1_x2,y2,1_x3,y3,1]
=0,0,1_2.8,2.1,1_4.3,4.4,1]
area=1/2[det a]
then Im stuck

10 answers

what, you can't find the determinant?
Those two zeros in the top row make it easy:

|A| = (2.8)(4.4)-(4.3)(2.1) = 3.29

Better review your determinants if this technique is going to come up often.
Ok I see I was not multiplying the right numbers. Thanks for clarifying for me.
do you think you could help me with this quiz?
The answer is 1.65mi^2
U5 L3 Determinates & Inverses

1. B, not possible
2. A, [ 1/0 4/3 ]
3. D, [ -3/-15 21/9 60/-45 ]
4. A, [ 6/-2 -14/-6 ]
5. A, [ 20/32 80/3]
6. D, undefined
7. A, yes
8. A, 1.65 mi²
9. B, [ 7/-2 25/-7 ]
10. B, Team 1
100% thank you
Søft Angɛƚ 100% correct
soft angel is still correct for connexus as of 4/21/22
r.i.p to samantha who couldnt get the answers
Søft Angɛƚ is my hero. Still correct as of 2022.