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.
Answer:
see below
Step-by-step explanation:
Standard equation for a circle with center h,k and radius r
(x-h)^2 + (y-k)^2 = r^2
so for this one center = (1,2) radius = 4
Answer: 108 degrees
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Explanation:
Angle ABC is given to be 90 degrees. By the converse of Thales Theorem, we know that AC is a diameter of the circle.
If we draw a line from A to C, it will pass through the center of the circle.
Therefore, arc AC is 180 degrees as this is half the distance around the circle.
minor arc AD = 72
minor arc CD = x
(minor arc AD) + (minor arc CD) = arc AC
72+x = 180
72+x-72 = 180-72
x = 108
minor arc CD is 108 degrees
Only D is correct, it intersects at 90 degrees so it cant be obtuse or acute and never intersecting would be parallel lines <span />