A midpoint is found by adding up two numbers and then dividing by 2 (Also known as an average). Therefore, a midpoint marks half of a line. That means that DP is 1/2 of DE. We can now form an equation. 6x + 4 = 1/2 * (14x - 10), making 6x + 4 = 7x - 5 by using the distributive property. Next, isolate x by subtracting by 6x on both sides and adding by 5 on both sides. You would get x = 5 + 4, which means that x = 9.
