Question

2 1) 1 9 y •(-2,3x)= 2) 3x+4y-4x-(-y)= 3 2 3) (5 20 - 4,2)+(3,11+ 1 5)=

Answer 1

1)
1/9y*(-2,3x)
-1/9*y*23/10x
-1/9y*23/10x
-23/90xy
2)
3x+4y-4x-(-y)=3/2
3x+4y-4x+y=1,5
-x+5y=1,5
-x=1,5-5y
x=-1,5+5y
x=-1,5+5y
3)
(5/20-4,2)+(3,11+1/5)
0,25-4,2)+(3,11+0,2)
(-3,95)+3,31
-3,95+3,31
-0,64

Answer 2

I assume that each number group separated by a comma represents a coordinate pair (x, y).

1. To evaluate the expression 1-9y•(-2,3x), we need to first calculate the dot product between the two vectors:

-9y • (-2,3x) = (-9y)(-2) + (-9y)(3x) = 18y - 27xy

Then we multiply the result by 1:

1(18y - 27xy) = 18y - 27xy

So the final answer is 18y - 27xy.

2. To simplify the expression 3x+4y-4x-(-y), we can combine like terms:

3x - 4x + 4y + y = -x + 5y

So the final answer is -x + 5y.

3. To add the two vectors (5,20-4.2) and (3,11+1.5), we can simply add the corresponding components:

(5,20-4.2) + (3,11+1.5) = (5+3,20-4.2+11+1.5) = (8, 27.3)

So the final answer is (8, 27.3).