Answer:
3X+5Y=68 MULTIPLY BY 4
3Y-4X=6 MULTIPLY BY 3 & ADD.
12X+20Y=272
-12X+9Y=18
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29Y=290
Y=290/29
Y=10 ANS.
Step-by-step explanation:
Hi, the answer is ;
Answer:
12 dimes and 27 nickels
Step-by-step explanation:
.05N + .1d = 2.55
N= 3d - 9
0.05 (3d-9) + 0.1d = 2.55
0.15d - 0.45 + 0.1d = 2.55
0.25d = 2.55 + 0.45
0.25d = 3
D = 12
N = 3 (12) - 9
N = 36 - 9
N = 27
The answer is D. y = -2x + 20. This is because it has a negative slope (-2x). When a number in a slope-intercept equation has the variable (x), that determines the positive or negative association. If it is a positive slope, it travels up from left to right. If it is a negative slope, it travels down from left to right.
I think is D , hope i answer fast enough haha :D
Perhaps the easiest way to find the midpoint between two given points is to average their coordinates: add them up and divide by 2.
A) The midpoint C' of AB is
.. (A +B)/2 = ((0, 0) +(m, n))/2 = ((0 +m)/2, (0 +n)/2) = (m/2, n/2) = C'
The midpoint B' is
.. (A +C)/2 = ((0, 0) +(p, 0))/2 = (p/2, 0) = B'
The midpoint A' is
.. (B +C)/2 = ((m, n) +(p, 0))/2 = ((m+p)/2, n/2) = A'
B) The slope of the line between (x1, y1) and (x2, y2) is given by
.. slope = (y2 -y1)/(x2 -x1)
Using the values for A and A', we have
.. slope = (n/2 -0)/((m+p)/2 -0) = n/(m+p)
C) We know the line goes through A = (0, 0), so we can write the point-slope form of the equation for AA' as
.. y -0 = (n/(m+p))*(x -0)
.. y = n*x/(m+p)
D) To show the point lies on the line, we can substitute its coordinates for x and y and see if we get something that looks true.
.. (x, y) = ((m+p)/3, n/3)
Putting these into our equation, we have
.. n/3 = n*((m+p)/3)/(m+p)
The expression on the right has factors of (m+p) that cancel*, so we end up with
.. n/3 = n/3 . . . . . . . true for any n
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* The only constraint is that (m+p) ≠ 0. Since m and p are both in the first quadrant, their sum must be non-zero and this constraint is satisfied.
The purpose of the exercise is to show that all three medians of a triangle intersect in a single point.