Answer:
-3
Step-by-step explanation:
y=mx+b where m=slope and b=y-intercept.
Step-by-step explanation:
because VW || YZ, the 2 triangles are similar.
this is given by the rules of equal angles of intersecting lines with parallel lines. Z to V and Y to W would be such intersecting lines.
and therefore, the angle at W is the angle at Y, the angle at V is the angle at Z. and therefore both angles at A are equal.
so, for similar triangles the scaling factor between corresponding pairs of sides is the same for all sides.
e.g. the same scaling factor that converts 7.2 to 12, converts then also x to x+4.
7.2 × f = 12
f = 12/7.2 = 12/ 72/10 = 120/72 = 10/6 = 5/3
x × 5/3 = x + 4
5x = 3x + 12
2x = 12
x = 6
A to Y = x = 6
W to A = x + 4 = 6 + 4 = 10
The next number is 14 I believe
Qr=1/2 mn = ms
mn=2 ms=12
ln^2=lm^2+mn^2 using phythagoras rule
ln^2=400
ln=20
If she went 10 miles upstream in the same time as she went 20 miles downstream, that means the downstream speed is twice the upstream speed.
The speed is still water is 9 mph.
The speed of the current is c.
Going downstream, the current adds speed, so the sped downstream is 9 + c.
The speed upstream is 9 - c.
9 + c is twice 9 - c.
9 + c = 2(9 - c)
9 + c = 18 - 2c
3c = 9
c = 3
Answer: The speed of the current is 3 mph.
Check:
9 + c = 12
9 - c = 6
By taking into the account the speed of the current, the downstream speed, 12 mph, is indeed twice the upstream sped, 6 mph.