Calculate x in Rectangular Area Equation: 2(x-4) by 2x+8 Yields 132
Question
The area of the rectangle below is 132.
Calculate x.
Video Solution
Solution Steps
00:00Find X
00:03Use the formula for calculating rectangle area (side times side)
00:09Substitute the side values according to the given data
00:19Substitute the area size according to the given data and solve for X
00:30Open parentheses properly
00:38Use the shortened multiplication formulas to expand the parentheses
00:59Calculate 2 squared and 8 squared
01:06Isolate X
01:23Take the square root to find the possible solutions for X
01:29And this is the solution to the problem
Step-by-Step Solution
To solve the problem, let's proceed with the following steps:
Step 1: Identify the area formula
Step 2: Substitute side expressions
Step 3: Simplify the equation and solve
Let's begin:
Step 1: The area of the rectangle is given by the formula: Area=Length×Width
For this rectangle, the length and width are given as 2x+8 and 2(x−4), respectively. Thus, we have the equation for the area:
(2x+8)×(2(x−4))=132
Step 2: Substitute the side expressions and set up the equation:
(2x+8)×(2x−8)=132
Step 3: Expand and solve:
First, we expand the expression using multiplication:
The side expression simplifies to a difference of squares:
(2x+8)(2x−8)=(2x)2−82=4x2−64
The area equation is:
4x2−64=132
Step 4: Simplify and solve the quadratic equation:
Add 64 to both sides to isolate the quadratic term:
4x2=196
Divide by 4:
x2=49
Take the square root:
x=±49x=±7
Therefore, the solutions for x are x=7 and x=−7. Since area is scalar, both positive and negative solutions are valid for x.