An isosceles trapezoid has base angles of 45° and bases of lengths 8 and 14. The area of the trapezoid is
hi
hey sup shadow
Let me draw this bad boy
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The area of a trapezoid is found using the following formula: \[A_{t} = \frac{ a+ b }{ 2 }h\]
a is 8, b is 14
We need h, or the height of the trapezoid
Are you familiar with trigonometry, or Sin/Cos/Tan?
not at all
Oi
Well it's a way of dealing with triangles. Pretty sure it's the easiest way to solve this, so I don't know why you'd get this problem without having learned it xd
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We draw a line and see our triangle take shape. Notice that the height of the triangle is the height of the trapezoid.
33 sq. units 33√2 sq. units 72 sq. units da answer choices i forgot to put earlier
There's an acronym for Sin/Cos/Tan that goes, SOH CAH TOA It stands for Sine = Opposite/Hypotenuse Cosine = Adjacent/Hypotenuse Tangent = Opposite/Adjacent
We'll use tan to look at the height of the triangle (opposite to the 45 degree angle), and the base of the triangle (adjacent to the 45).
We find the base by subtracting 8 from 14 Getting this area ->|dw:1576600227577:dw|
\[\tan 45 = \frac{ x }{ 6 }\]
Or we could use big brain and realize that an isosceles triangle is a triangle with two equal sides. Lol
So the base of the triangle is the same length as the height of the triangle. You don't need trig identities.
That's just not graphically depicted in what I drew. Sorry, no sleeps :P
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\(\color{#0cbb34}{\text{Originally Posted by}}\) @Shadow The area of a trapezoid is found using the following formula: \[A_{t} = \frac{ a+ b }{ 2 }h\] \(\color{#0cbb34}{\text{End of Quote}}\) a is 8, b is 14, h is 6
Input and you get your answer.
@uhfinn you followed all that?
Hmm actually, that doesn't come out right.
yea i ddidnt get da right answer
I got it don't worry
So I forgot that there's two triangles in our trapezoid lol
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This is why for geometry problems, it's helpful to draw it all out.
So to get the base of one side triangle of a trapezoid, do (bottom - top)/2
Input that new height and you should be good
ok got it thank you shadow ur so cool and awesome ur awesome thanks
np
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