500 = 35x+50
450 = 35x
450/35 = x
12.85 = x
12 lessons
Answer:
25 degrees
Step-by-step explanation:
vertical angle 63 make oposite lines form a 63 degree angle. You need to find s. Now subtract 38 from 63, so 63-38 = 25 degrees
Add 5/7 on both sides.
It'll cancel out the negative 5/7, and it will make the x variable only equal to one number (Well, a mixed number.)
Answer:
C. O.5s
Step-by-step explanation:
If the wave length is 100m and it goes at a speed of 200m/s then it will only take 0.5 seconds because 100 is half of the speed of 200
The minimum distance will be along a perpendicular line to the river that passes through the point (7,5)
4x+3y=12
3y=-4x+12
y=-4x/3+12/3
So a line perpendicular to the bank will be:
y=3x/4+b, and we need it to pass through (7,5) so
5=3(7)/4+b
5=21/4+b
20/4-21/4=b
-1/4=b so the perpendicular line is:
y=3x/4-1/4
So now we want to know the point where this perpendicular line meets with the river bank. When it does y=y so we can say:
(3x-1)/4=(-4x+12)/3 cross multiply
3(3x-1)=4(-4x+12)
9x-3=-16x+48
25x=51
x=51/25
x=2.04
y=(3x-1)/4
y=(3*2.04-1)/4
y=1.28
So now that we know the point on the river that is closest to Avery we can calculate his distance from that point...
d^2=(x2-x1)^2+(y2-y1)^2
d^2=(7-2.04)^2+(5-1.28)^2
d^2=38.44
d=√38.44
d=6.2 units
Since he can run at 10 uph...
t=d/v
t=6.2/10
t=0.62 hours (37 min 12 sec)
So it will take him 0.62 hours or 37 minutes and 12 seconds for him to reach the river.