Hope this helps with the answer to your question:)
Answer:
2/13
Step-by-step explanation:
In a deck of 52 cards, there are 2 sets of red cards. Diamonds and Hearts. In each set of red cards, there are 4 fives. If there are 2 sets, that means that there are 8 red fives in the deck of 52 cards. This means that the probability is 8/52 which is simplified into 2/13.
Step-by-step explanation:
substitute for y
x+3+4 = -6x
x+ 7 = -6x
7 = -7x
-1 = x
y = -1+3
y = 2
<h3>Rate of the boat in still water is 70 km/hr and rate of the current is 15 km/hr</h3><h3><u>Solution:</u></h3>
Given that,
A motorboat travels 165 kilometers in 3 hours going upstream and 510 kilometers in 6 hours going downstream
Therefore,
Upstream distance = 165 km
Upstream time = 3 hours
<h3><u>Find upstream speed:</u></h3>

Thus upstream speed is 55 km per hour
Downstream distance = 510 km
Downstream time = 6 hours
<h3><u>Find downstream speed:</u></h3>

Thus downstream speed is 85 km per hour
<em><u>If the speed of a boat in still water is u km/hr and the speed of the stream is v km/hr, then</u></em>
Speed downstream = u + v km/hr
Speed upstream = u - v km/hr
Therefore,
u + v = 85 ----- eqn 1
u - v = 55 ----- eqn 2
Solve both
Add them
u + v + u - v = 85 + 55
2u = 140
u = 70
<em><u>Substitute u = 70 in eqn 1</u></em>
70 + v = 85
v = 85 - 70
v = 15
Thus rate of the boat in still water is 70 km/hr and rate of the current is 15 km/hr
Direction vector of line of intersection of two planes is the cross product of the normal vectors of the planes, namely
p1: x+y+z=2
p2: x+7y+7z=2
and the corresponding normal vectors are: (equiv. to coeff. of the plane)
n1:<1,1,1>
n2:<1,7,7>
The cross product n1 x n2
vl=
i j l
1 1 1
1 7 7
=<7-7, 1-7, 7-1>
=<0,-6,6>
Simplify by reducing length by a factor of 6
vl=<0,-1,1>
By observing the equations of the two planes, we see that (2,0,0) is a point on the intersection, because this points satisfies both plane equations.
Thus the parametric equation of the line is
L: (2,0,0)+t(0,-1,1)
or
L: x=2, y=-t, z=t