Mô tả phương pháp chung của bài toán tìm khoảng ước lượng tham số. Giúp mình với ạ

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15

On a piece of paper, graph y< x-1. then determine which answer choicematches the graph you drew.13. z3. 2(3.290-1)

Use the spider tool located on page 1 of this activity to draw a 12-pointed star for the new logo. (hint: if the spider rotates 360 degrees -- or 720 degrees or 1080 degrees -- she will be facing in the same direction in which she started. when the spider is done drawing, you want her to be facing in the same direction in which she started. she'll be making 12 rotations, all the same size, so each rotation must be some multiple of 360/12 = 30 degrees.) urgently. been stuck on this problem for around 45 minutes now.! it should be easy if you're smart enough