The described picture frame can be visualized into two separate parts. The first area is equal to the area using the outermost dimensions for the length and width.
Area = Length x Height
Area = (20 in) x (14 in)
Area = 280 in²
We are given that the area is only equal to 192 in². We subtract this value from the computed area.
Difference = 280 in² - 192 in²
difference = 88 in²
This area is equal to the area of the hollow space inside the frame. That is equal to,
height = 20 in - 2x
length = 14 in - 2x
The area,
88 = (20 - 2x)(14 - 2x)
Simplify the right hand side of the equation.
88 = 280 - 68x + 4x²
Divide the equation by 4,
22 = 70 - 17x + x²
Transposing,
x² - 17x - 48 = 0
The factors of the equation is 58.2.
Thus, the thickenss is equal to 58.2 in
Answer:
We have been given an equation 
We will factorize it by middle term splitting.
Step 1: 
Taking common factors out by clubing first two terms ad last two terms
Step 2: 
Step 3: 
Equating both above factors to zero as:
Step 4: 
And 
.
All the answers are on the image attached. there is no work cause i did mental math. the answer to the riddle is typed in yellow at the bottom of the picture
0.3*42 this gives you a 30% discount
3/10*42 this gives you a 30% discount
0.03*42 this gives you a 3% discount
3 *4.2 This is not a discount
