Answer: Choice D
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Explanation:
It might help to turn the image sideways so that it is rotated 90 degrees. Have the triangle facing upward with (x1,y2) and (x1,y1) as the base points. The base has a length of (y2-y1) as this is the difference of y coordinate values. The x coordinate being the same indicates we simply subtract.
The height is (x3-x1) which is the difference of the x coordinates for either left point and the right point
So,
area = (1/2)*base*height
area = (1/2)*(y2-y1)*(x3-x1)
which is why choice D is the answer
Answer:
3
Step-by-step explanation:
do the stuff inside the parentheses
*double negatives become positives*
6*2=12
-9+12
=3
pls mark me brainliest
Answer:
x= 7.5 mile/h
y= 3.5 miles / h
Step-by-step explanation:
Given x and y
so, x+y = speed down river
and x-y= speed up river
using
travel time = distance / speed for each case;
we get;
22/x+y=2 ---(1)
and
22/x-y=5.5 -----(2)
Solving equations simultaneously
eq 1 gives
2x+2y=22 ---(3)
eq 2 gives
5.5x-5.5y=22 ----(4)
Multiply eq 3 by 2.75
==> 5.5x+5.5y=60.5 --- (5)
adding eq 4 with eq 5
==> 11x =82.5
==> x= 7.5 miles/h
put this value in eq 3
==> 2(7.5)+2y=22
==> 2y=22-19.8
==> 2y=7
==> y = 3.5
Answer: 52.94
Step-by-step explanation:
Length of train A = 480m
Tunnel length = 1320m
Time taken to cross tunnel = 2 mins = 120sec
Length of train B = 420m
Train B is slower than train A
Difference between their speed = 18km/hr
18km/hr = (18×1000)/3600 = 5m/s
Speed of train A :
Speed = distance / time
Speed = 1320 / 120 = 11m/s
Therefore, speed of train B :
(11 - 5)m/s = 6m/s
Relative speed of the two trains is therefore;
(Speed of A + speed of B)
Note : they are moving in opposite direction
( 11 + 6)m/s = 17m/s
Therefore time taken to cross each other :
(Sum of the length of both trains / relative speed of the trains)
Time taken = (480m + 420m) / (17m/s)
Time taken = 900m / 17m/s
Time taken = 52.94s
Answer:
A: W = 8x
B: 12y + 320
C: 44
Step-by-step explanation:
A: Lana can make $8 an hour.
W = 8x
B: She makes $12 per hour for every hour of overtime. This means that she already worked 40 hours with regular pay. She has already made $320.
40 × $8 = $320
S = 12y + 320
C: Plug in the amount Lana earned into the second equation. The second equation will account for pay from both regular and overtime hours.
S = 12y + 320
368 = 12y + 320
368 - 320 = (12y + 320) - 320
48 = 12y
48/12 = (12y)/12
4 = y
y = 4
Lana worked 4 hours of overtime and 40 hours of regular hours. In total, she worked 44 hours.
4 + 40 = 44
