Recall that given vectors a and b, they are perpendicular if and only if $a\cdot b$ =0. If $a=(a_1,a_2),b=(b_1,b_2)$ . Then $a\cdot b = a_1b1_+a_2b_2$ .

IN our case a=(5,-1,2) and b) (1,-3,-4). So,

$a\cdot b = 5\cdot 1 + (-1)\cdot(-3) + 2\cdot(-4) = 5+3-8 =0$

So both gears are perpendicular.

3 0

2 years ago

Help me plzzzzzzzzzzzz

Ad libitum [116K]

Looking at the triangle we see the angles:

58, x

We also see a right angle, therefore you now have:

90, 58, 0

All three angles of a triangle should have a total of 180 degrees, so we add the known angles and subtract the total from 180.

90 + 58 = 148

180 - 148 = 32

Therefore, x = 32 or C

3 0

2 years ago

What is the reason that absolute value is always written as a positive?

trapecia [35]

Answer:

Absolute value is talking about distance (Distance from zero); distance is always measured by positive numbers.

5 0

2 years ago

If x=6 and y=−2, evaluate the following expression:2xy​

If x=6 and y=−2, evaluate the following expression:2xy