Respuesta :

Answer:

A - x = 4

Step-by-step explanation:

According to The Midsegment Trapezoid Theorem the length of the midsegment is the sum of both bases divided by 2.

So to find the value of x:

x + 3 + 4x  7 = 15*2  add like terms

5x + 10 = 30 subtract 10 from both sides

5x = 20 divide both sides by 5

x = 4