You've got five different problems in this photo ... four on top and the word problem on the bottom ... and they're all exactly the same thing: Taking two points and finding the slope of the line that goes through them.
In every case, the procedure is the same.
If the two points are (x₁ , y₁) and (x₂ , y₂) , then
the slope of the line that goes through them is
Slope = (y₂ - y₁) / (x₂ - x₁) .
This is important, and you should memorize it.
#1). (8, 10) and (-7, 14)
Slope = (14 - 10) / (-7 - 8) = 4 / -15
#2). (-3, 1) and (-17, 2)
Slope = (2 - 1) / (-17 - -3) = (2 - 1) / (-17 + 3) = 1 / -14
#3). (-20, -4) and (-12, -10)
Slope = [ -10 - (-4) ] / [ -12 - (-20) ]
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The word problem:
This question only gives you one point on the graph,
and then it wants to know what's the slope ?
What are you going to do for another point ?
A "proportional relationship" always passes through the origin,
so another point on the line is (0, 0) .
Now you have two points on THAT line too, and you can easily
find its slope.
The volume of a rectangular prism is:
V=xyz where x,y,z are the dimensions...
In this case:
V=5*(2 1/2)*(1 1/2)
which is equal to
V=(12 1/2)*(1 1/2)
So the top one and the third one down are the correct volume.
Answer:
D) a = - 5/2
Step-by-step explanation:
2x -5y - 7 = 0
5y = 2x - 7
y = 2/5 x - 7
the slope of this line is therefore 2/5 (factor of x).
the perpendicular slope is then (exchange y and x and flip the sign) -5/2, which is then a and the factor of x.
