Answer:
Step-by-step explanation:
7.
Speed = Distance / time
Distance is fixed so speed x time = constant
speed1 x time1 = speed2 x time2
speed1/speed2 = time2/time1
speed1/speed2 = 20/27
time2/time1 = 20/27
Percentage decrease in time = (time1 - time2)/time1 x 100%
= (1 - time2/time1) x 100%
= (1 - 20/27) x 100%
= 7/27 x 100%
= 25.9%
8.
Let the equation of the angle bisector be y = mx + C
It is the angle bisector so its slope, m, is half way between slope of the two lines:
y = 2; slope = 0
y = 4x - 2; slope = 4
So m = (0 + 4) / 2 = 2
y = 2x + C
It is the angle bisector so the line must pass through intersection of the two lines:
y = 2 and y = 4x - 2
4x -2 = 2
x = 1
Intersection point is at x = 1 and y = 2
Substitute back into y = 2x + C
2 = 2(1) + C
C = 0
So the equation is y = 2x
9.
= 1/±5
= ±1/5