find the value of t in the diagram
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In a trapezoid, with bases [tex] b [/tex] and [tex] B [/tex] and height [tex] h [/tex], the area is given by
[tex] A = \frac{(B+b)h}{2} [/tex]
In your case:
[tex] B = BC = 3t [/tex]
[tex] b = AD = t [/tex]
[tex] h = AB = t [/tex]
so, the formula becomes
[tex] A = \frac{(3t+t)t}{2} = \frac{4t^2}{2} = 2t^2 [/tex]
Since the area is [tex] 50 \text{cm}^2 [/tex], we have
[tex] 2t^2 = 50 \iff t^2 = 25 \iff t = 5 [/tex]
Answer
5 cm
Explanation
The figure shown is a trapezium.
The area of a trapezium is given by;
Area = 1/2 h( a+b)
Where h ⇒perpendicular distance between the two parallel sides
a and b ⇒length of the parallel sides.
h = t
a =t
b = 3t
1/2 t(t+3t) = 50
1/2 ×t × 4t = 50
1/2 ×4t²=50
2t² = 50
dividing both sides by 2
t² = 25
t = √25
= 5 cm