Question

practice d: (first taught in lesson 55) find y. after you enter your answer press go. y =

Explanation:

Step1: Apply the mid - segment theorem

The mid - segment of a triangle is parallel to the third side and half its length. Here, \(DE\) is the mid - segment of \(\triangle ABC\), so \(3y=\frac{1}{2}(11y - 20)\)

Step2: Solve the equation

Multiply both sides of the equation \(3y=\frac{1}{2}(11y - 20)\) by \(2\) to get \(6y = 11y-20\).
Subtract \(6y\) from both sides: \(0=11y - 6y-20\), which simplifies to \(0 = 5y-20\).
Add \(20\) to both sides: \(20 = 5y\).
Divide both sides by \(5\): \(y = 4\)

Answer:

\(y = 4\)