Suppose $\triangle DEF$ is isosceles and $\overline{DE}$ is twice the length of $\overline{EF}.$ If the triangle has perimeter $80,$ how long is the shortest side?

Step-by-step explanation:

5

y = 2x

step-by-step explanation:

if you divide each number in the sequence, you'll see that they all have a multiple factor of 2. each number in the series, and any other numbers which may continue, will be multiplied by 2. therefore, y is the next number in the sequence, and x is the current one, so, our formula will be y = 2x.