Answer:
x=±9 and y=10
Step-by-step explanation:
so for x
we have
x²+(-4)=32
x²=36
x=±9
for y:
y+y-4=y+6
2y-4=y+6
y=10
I love these. It's often called the Shoelace Formula. It actually works for the area of any 2D polygon.
We can derive it by first imagining our triangle in the first quadrant, one vertex at the origin, one at (a,b), one at (c,d), with (0,0),(a,b),(c,d) in counterclockwise order.
Our triangle is inscribed in the 
rectangle. There are three right triangles in that rectangle that aren't part of our triangle. When we subtract the area of the right triangles from the area of the rectangle we're left with the area S of our triangle.
That's the cross product in the purest form. When we're away from the origin, a arbitrary triangle with vertices 
will have the same area as one whose vertex C is translated to the origin.
We set 
That's a perfectly useful formula right there. But it's usually multiplied out:
That's the usual form, the sum of cross products. Let's line up our numbers to make it easier.
(1, 2), (3, 4), (−7, 7)
(−7, 7),(1, 2), (3, 4),
[tex]A = \frac 1 2 ( 1(7)-2(-7) + 3(2)-4(1) + -7(4) - (7)(3)
Answer: Ok first if you read the directions read them again, then you look at the problem carefully and make an equation that should look close to this: 0.75xp=c, Once you have that equation you have to replace the p with a 2 and multiply to get an answer of 1.50. The second part would be taking 0.5x2 which is easy it would be 0.10 then you take that and minus it from the total of the last problem which would get you to $1.40
Step-by-step explanation:
Answer:
For vectors given by their components: A = (Ax, Ay, Az) and B = (Bx, By, Bz), the scalar product is given by A · B = AxBx + AyBy + AzBz Note that if θ = 90°, then cos (θ) = 0 and therefore we can state that: Two vectors, with magnitudes not equal to zero, are perpendicular if and only if their scalar product is equal to zero.
Step-by-step explanation:
