Solve the system of equations by finding the reduced row-echelon form of the augmented matirix for the system of equations. a. (-3,7,3) c. (-9,1,-3) b. (1,1,-9) d. (3,7,-3) Please select the best answer from the choices provided A B C D Mark this and return

d

step-by-step explanation:

hello and welcome!

so, when we see the words "proportional" along with a table, we need to know that we're looking numbers that divide by the same thing.

looking at this table, we simply have to do a trial and error, and divide to see which numbers have the same quotient. if you look at choice a & c, they both have equal quotients for three of the numbers, with one exception, so those can't be the answer. looking at b, there is no similarity, so that can't be it. then, we see d; if you divide all the numbers in the table, you'll see that they all divide by two, which is a proportional relationship, and our answer!

also, always remember that the x will always be the number that goes into y, and somewhere behind this table, is a formula. for this specific table, the formula would be:

since our x-value is being divided by two to get the y-value. and if they were to ask for more numbers in the series, this is the formula you would use to find them.

the answer is: 5,953.2 mm²

you have the  8-sided octahedron as a composite figure that has 2 square pyramids. so, you should   apply the formula for the calculated area of a square pyramid as so:   a=s²+2sl

  a is the area of the square pyramid.

  s will be the base of the square pyramid (s = 33 mm).

  l is the slant height of the square pyramid (l = 28.6 mm).

then, when you substitute these values into the formula you get:

  a=s²+2sl

  a=(33 mm)²+2(33 mm)(28.6 mm)

  a=1089 mm²+1887.6 mm²

  a=2,976.6 mm²

thus, the area of the  surface area of the octahedron is:

sa = 2a

sa = 2(2,976.6 mm²)

sa = 5,953.2 mm²

thus the answer will be: 5,953.2 mm²