The work of a student to find the dimensions of a rectangle of area 8 + 12x and width 4 is shown below: Step 1: 8+12x Step 2: 4(4) +4(8x) Step 3: 4(4+8x) Step 4: Dimensions of the rectangle are 4 and 4+8x In which step did the student first make an error and what is the correct step? a. Step 2;4(2)+4x(2)
b. Step 2;4(2)+4(3x)
c. Step 3;4+(4+8x)
d. Step 3;4+(4•8x)

PLEASE LEAVE EXPLENATION!! :)

Step (2) is incorrect.

Step-by-step explanation:

The area of a rectangle is given by :

A = length × width

Area = 8+12x

Width = 4

Step 1: 8 + 12x  

Step 2: 4(2) + 4(3x)  

Step 3: 4(2 + 3x)  

Step 4: Dimensions of the rectangle are 4 and 2 + 3x.

It means he has done a mistake in step (2). The correct step should be 4(2) + 4(3x).

answer: city needs 2.4 inches of rainfall more to match the record of 40 inches.

step-by-step explanation:

since we have given that

total annual rainfall a city record = 40 inches

this year, total rainfall recorded = 37.6 inches

number of inches of rainfall   is needed to match the record of 40 inches is given by

hence, city needs 2.4 inches of rainfall more to match the record of 40 inches.

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.