Ineed with this geometry question!

A property of a parallelogram is that their diagonals bisect eachother. Since in part a the diagonals bisect eachother, we know for sure that it's a parallelogram.

We also know that you can make two congruent triangles with a parallelogram. Note that if you draw a line from one accute angle to the other, we create two equal triangles by SAS congruency, so since the figure is comprised of two congruent triangles, it is a parallelogram.

walter needs to make at least 5 more cookies but no more than 40. 5 ≤ x ≤ 40

step-by-step explanation:

20 ≤ x + 15 ≤ 55

subtract 15 from all parts

20-15 ≤ x + 15-15 ≤ 55-15

5 ≤ x ≤ 40

this means how many more cookies he has to make

walter needs to make at least 5 more cookies, but no more than 40 cookies; 5 ≤ x ≤ 40