Answer:
25%
Step-by-step explanation:
Let v, t be the current average speed and the time taken to reach the school respectively.
As distance = speed x time, so,
distance, d=vt...(i)
Let V be the new average speed in order to to take 20% less time than t.
So, time taken with speed V = t-20% of t = t- 0.2t= 0.8t
As distance is constant, so
d= V(0.8t)= 0.8Vt
hBy using equation (i), we have
0.8Vt = vt
0.8 V = v
V= v/0.8=1.25v
Therefore, the percentage increase in the average speed = 

=25%
Hence, the percentage increase in the average speed is 25%.
Answer:
y=[-4]x+[10]
Step-by-step explanation:
For a line to be perpendicular to another it must have the reverse reciprocal of the opposite line, to find the reverse reciprocal you take your slope, flip the numerator and denominator, and multiply it by -1.
The slope
turns into
and is then multiplied by -1 to become
which can be simplified down to: 
Now that we know the slope we need the line to pass through a point, so we will use point slope form:

Substitute in our slope and point values:

Now solve for y:

Then you will find that line
runs perpendicular to
and intersects point (2,2).
You got divide só see mean, the middle number is the median, range you add all number and divide but how many number has
x² + 7x - 4 = 0
a = 1, b = 7, c = -4
x = [-b +/- √(b² - 4ac)]/2a
= [-7 +/- √(49 + 4)]/2
= (-7 +/- √53)/2