Use dot product
a=(x1,y1) and b=(x2,y2)
a.b=/a/*/b/ cos x
a.b mean dot product of two vectors
a.b is equals x1*y1+x2*y2
Answer:
the sume of two numbers is 2. if one number is subtracted from the other, their difference is 8. find the numbers---->
Step-by-step explanation:
X+Y=2
X-Y=8
If you subtract X+Y with X-Y, you get 2y, and so that equals 2-8, that is -6.
2y=-6
y=(-6)/2
y=-3
-3+X=2
x=2+3
x=5 and y=-8
Check
-3+5=2
5-(-3)=8
Answer:
x=9.2
Step-by-step explanation:
23/x=17.5/7
cross multiply
17.5x=161
divide
x=9.2
Answer:
The perpendicular equation is y = -3x -21
Step-by-step explanation:
Perpendicular lines have the exact opposite slope as the other equation and they never have the same y-intercept.
To find the perpendicular slope just look at the slope in the original equation and get the exact opposite.
First let's simplify the equation.
-5 + x = 3y (divide by 3 on both sides to get y by itself)
-5/3 + 1/3x = y or y = 1/3x + 5/3
The exact opposite of this slope would be -3.
Now plug in the point you were given so that we can find the y-intercept.
6 = -3(-9) + b (b = y-intercept)
6 = 27 + b (subtract 27 on both sides)
-21 = b
So the perpendicular equation looks like this.
y = -3x -21
Answer:

Step-by-step explanation:
1) To find the 4th term given the Explicit Formula, i.e. definition, just plug it in. The common difference according to question is 4, the 1st term is 3.

2) For this another Sequence in Explicit definition we just need to plug it in:
