We have that
<span>y=3x</span>²<span>+18x-21
using a graph tool
see the attached figure
the solutions are
x=-7x=1</span>
<h3>
Answer: Choice D. 4^2+5^2 = x^2</h3>
See note at the bottom
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The entire building is 20 feet. Fifteen feet of that is from the ground to the first landing of the stairs or fire escape. So 20-15 = 5 feet represents the height of the second set of stairs (leading to the roof of the building)
The base of the triangle is 4 feet as shown in the diagram. The height is 5 feet as found in the prior paragraph. Use the pythagorean theorem to say
a^2 + b^2 = c^2
4^2 + 5^2 = x^2
Note: If you meant to write 4^2+5^2 = x^2 for choice D, then that would be the answer. Otherwise, there is a typo somewhere.
Instead of typing it all on here, I included my explanations with the work.
Answer:
m = 4
Step-by-step explanation:
tan ( y ) = 10 / 8
tan ( y ) = 5 / 4
tan ( y ) = 1.25
y = 51.4 degrees ( approximately )