A boy stands 1 meter away from a lamppost. He is 1.8 meters tall and casts a shadow 2 meters long in the light from the lamp
The diagram is attached below using the given information
We have two similar triangle
Triangle ACD is similar to triangle ABE. So the sides are in proportional

AC = AB + BC = 3m

2x = 1.8 * 3 (cross multiply)
2x = 5.4
Divide by 2 on both sides
x = 2.7
Height of Lamppost is 2.7 meter
So if y=-5x-23 then we can plug that value in for y in x-10y=6, so it becomes
x-10(-5x-23)=6
x+50x+230=6
51x=-224
x=-4.39
plug this x value into the equation y=-5x-23
y=-5(-4.39)-23
y=21.95-23
y=-1.05
Correct answer:
"<span>If the sum of the squares of the two shorter sides equals the square of the longest side, then the triangle is a right triangle"
the Pythagorean theorem states that in a right triangle, the sum of the squares of the shortest sides is equal to the square of the largest side, the hypotenuse.
Also,
If we have a triangle with side lengths a, b and c, where a and b are the shortest, and "a squared plus b squared = c squared" then the triangle is a right triangle.
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Sure I can help you.
First and foremost, your graph shows that the slope is 0 since the equation of this graph is y= 4. We can also say that whatever the input is, it will always give you the same output. Therefore the output is just the same all through out.
Hope this helps !
Photon