When x = - 4 then
y = 1/2(-4) -6
y = -2 - 6
y = -8
solution (-4, -8)
answer is
B. (-4, -8) second choice
To find the magnitude of a vector, take the components, square them, then add them, then take the square root. This is very similar to the Pythagorean Theorem.
For your particular problem, I’ve included a picture showing how that specific calculation is done. :)
Circumference: 2πr C=18 so r= 18/2π= 9π
Arc length = rθ 6=(9π)θ θ=6/9π
Convert to degrees by multiplying by 180/π
6/9π x 180/π = 120 degrees
Cause 400 divided by 10 is 40