It's C the missing side is 9 units long so since cosine is adjacent divided by hypotenuse it would be 9/41
Let x=ab=ac, and y=bc, and z=ad.
Since the perimeter of the triangle abc is 36, you have:
Perimeter of abc = 36
ab + ac + bc = 36
x + x + y = 36
(eq. 1) 2x + y = 36
The triangle is isosceles (it has two sides with equal length: ab and ac). The line perpendicular to the third side (bc) from the opposite vertex (a), divides that third side into two equal halves: the point d is the middle point of bc. This is a property of isosceles triangles, which is easily shown by similarity.
Hence, we have that bd = dc = bc/2 = y/2 (remember we called bc = y).
The perimeter of the triangle abd is 30:
Permiter of abd = 30
ab + bd + ad = 30
x + y/2 + z =30
(eq. 2) 2x + y + 2z = 60
So, we have two equations on x, y and z:
(eq.1) 2x + y = 36
(eq.2) 2x + y + 2z = 60
Substitute 2x + y by 36 from (eq.1) in (eq.2):
(eq.2') 36 + 2z = 60
And solve for z:
36 + 2z = 60 => 2z = 60 - 36 => 2z = 24 => z = 12
The measure of ad is 12.
If you prefer a less algebraic reasoning:
- The perimeter of abd is half the perimeter of abc plus the length of ad (since you have "cut" the triangle abc in two halves to obtain the triangle abd).
- Then, ad is the difference between the perimeter of abd and half the perimeter of abc:
ad = 30 - (36/2) = 30 - 18 = 12
Answer:
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Step-by-step explanation:
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Answer:
the slope of the line in the graph is: 3
the y-intercept is: -4
the equation of the line is: y=3x-4
Step-by-step explanation:
If we find a point on the graph and count it until it reaches other solid point we get that you have to go up three and to the right by one. This solid point I looked at was (0,-4) and counted up to (-1,1). To find the slope, we have to simply count and use "rise over run". The rise is 3 for every 1 we run, making the slope 3/1 which is 3.
the y-intercept is the point on the graph that touches the y-axis on the graph. The only point on the graph that touches the y-axis is -4, making the y-intercept -4.
The equation for a graph is y=mx+b. m would be the slope and b would be the y-intercept. We know that the slope is 3 (m) and that the y-intercept is -4 (b). Putting them together, we get that the equation of the graph is y=3x-4.