I´d say "d" is the distance from the eye to the wall.
Now substracting 1.2-1 you´ll get the distance of the wall of the smallest triangle = 0.2 And you do 1.5-0.2= 0.3 that´s the distance of the wall of the other triangle. Then you solve everything with Pitagoras theorem. You have 2 rectangle triangles.
B+alfa=45°
tan^-1(0.2/d)=B
tan^-1(1.3/d)=alfa
THEN:
tan^-1(0.2/d)+tan^-1(1.3/d)=45°
Now you have 3 ecs and 3 variables.
alfa,B and "d"
X^2-2x -3 =0
a =1 b =-2 and c = -3
x = - (-2) +/- sqrt (-2)^2 - 4(1)(-3)
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2(1)
x = + 2 +/- sqrt [(4) - 4(-3)]
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2
x = +2 +/- sqrt [4 + 12]
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2
x = +2 +/- sqrt[16]
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2
x = +2 +/- (4)
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2
x = 2 + 4 or 2 -4
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2 2
x = 6/2 or -2/2
x = 3 or x = -1
Make two shapes out of it.
The bottom is a rectangle 14 x 5 = 70 square cm
The top is a triangle 1/2 x 12 x 5 = 30 square cm
Total area = 70 + 30 = 100 square cm
Answer:
These are all equivalent to the ratio of 1:2
Step-by-step explanation: