Answer:

Step-by-step explanation:
We are given the line y=2x+8. It is in slope-intercept form or y= mx+b, where m is the slope and b is the y-intercept.
The slope of the line is 2.
We want to find the equation that is perpendicular. Perpendicular lines have negative reciprocal slopes.
1. Negate
- Negate the slope, or switch the sign
- (+) 2 --> -2
2. Reciprocal
- Flip the numerator and denominator of the slope.
The perpendicular slope is -1/2, so the correct equation must be B.
Answer:
cos(m∠B) = 2√5/5
Step-by-step explanation:
Easiest way is to guess and check on this problem. When you take the cos(m∠B), you would get 6/3√5, rationalized to 2√5/5. That would be the correct answer.
= 16 + 49 - 3(11) - 4(10)
= 16 + 49 - 33 - 40
= -8
-1 <span>± </span><span><span>√61 / 6. Negative 1, plus or minus square root of 61 divide by 6</span></span>