Q:

abcd is an isosceles trapezoid with legs AB and CD and base BC. If the length of AB is 7y-4, the length of BC s 4y-6 and the length of CD is 8y-18, find the value of y. 30 points for brainliest!

Accepted Solution

A:
We are told that the legs of the isosceles trapezoid are AB and CD

AB = 7y - 4
CD = 8y - 18

In any isosceles trapezoid, the two legs are of equal length.
Therefore, AB = CD

⇒ 7y - 4 = 8y - 18

Add 18 to both sides of the equation
7y - 4 + 18 = 8y - 18 + 18
7y + 14 = 8y

Subtract 7y from both sides of the equation
7y - 7y + 14 = 8y - 7y
14 = y
⇒ y = 14