Hear help do it right plz

The fence around a quadrilateral-shaped pasture is 3a^2+15a+9 long. three sides of the fence have the following lengths: 5a, 10a-2, a^2-7. what is the length of the fourth side of the fence?

Solve the problem by using a venn diagram a group of students were surveyed about their taste in music.they were asked how they like three types of music: rock, country western and jazz.the results are summarized below: no one dislikes all three types of music.six like all three types of music.eleven don’t like country western.sixteen like jazz.three like country western and jazz, but not rock.six don’t like rock.eight like rock and country western.seven don’t like jazz.how many students were surveyed?

The volume of a rectangular prism is found by multiplying the length, width, and height of the prism. a rectangular prism has a width of 5x^2units, a length of 7x^3 units and a height of 2x^4 units. which is the volume of the prism in terms of x?