Respuesta :

Answer:

y = -1/3

Step-by-step explanation:

Isosceles trapezoids have legs that are the same length

AB = CD

7y-4 = 4y-5

Subtract 4y from each side

7y-4-4y = 4y-5-4y

3y -4 = -5

Add 4 to each side

3y -4+4 = -5+4

3y = -1

Divide by 3

3y/3 = -1/3

y = -1/3

Step-by-step explanation:

an isoceles trapezoid means that both legs (the sides left and right) are of equal length.

the length of the baseline does not matter at all (I guess, it is given here to confuse us or for follow up questions).

so, we know that AB = CD.

and therefore

7y - 4 = 8y - 18

-4 = y - 18

14 = y