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3 years ago

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1. A 30 ft. ladder is leaning against a building. The ladder reaches the bottom of a window that is located 15 ft. above the gro

und. What angle does the ladder make with the ground?

1 answer:

____ [38]3 years ago

8 0

Answer: 30°

Step-by-step explanation:

1. You know that:

- The length of the ladder is 30 feet.

- The window is located 15 feet above the ground.

2. Then, you can draw a right triangle as the one shown in the figure attached. So, you can calculate the angle asked as following:

$sin^{-1}\alpha=\frac{opposite}{hypotenuse}$

Where:

α: the angle of the ladder with the ground.

opposite=15 feet

hypotenuse=30 feet

3. When you substitute values, you obtain:

$sin^{-1}\alpha=\frac{15}{30}$

$\alpha=30$ °

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We know that when x=1, y=3 for the point. But we need to find what does y equal when x=1 for the line?

we'll go back to our equation of the line and use x=1.

$y=m(1)-2m+4$

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to find the vertical distance we'll subtract the y-coordinates of each point.

$d_1=3-(-m+4)$

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we'll do the same as above here:

$y=m(2)-2m+4$

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