PLEASE ANSWER WILL MARK BRAINLIEST!! The table shows the soil density of several soil samples at different depths.

(a) Write the quadratic regression equation that models the data. Let x = depth below the surface
and let y = soil density.
(b) Use the equation to estimate the soil density of a sample at a depth of 20 m. Show your work.

(a) y = -0.4931x² + 23.3798x + 996.0289

(b) x = 20

y = -0.4931x² + 23.3798x + 996.0289

y = -0.4931(20)² + 23.3798(20) + 996.0289

y = -0.4931(400) + 467.596 + 996.0289

y = -197.24 + 467.596 + 996.0289

y = 1266.3849

area = length x width

length = 2 x width

32 = 2 x width x width

32 = 2 x width^2

36 = width ^2  

width = 6

length = 12

area is 32

perimeter = 2 x 12 + 2 x 6 = 24 + 12 = 36

step-by-step explanation:

step-by-step explanation:

step 1: solve one of the equations for one of the variables. let's solve the first equation for y:

step 2: substitute that equation into the other equation, and solve for x.

step 3: substitute x = 4 x = 4 x=4 into one of the original equations, and solve for y.