A.
W = x + 5
A = W ∙ L
3 x² + 7 x - 40 = ( x + 5 ) ∙ L
L = ( 3 x² + 7 x - 40 ) / ( x + 5 )
L = 3 x - 8
Question B does not make sense.
When x = 2
A = 3 x² + 7 x - 40 = 3 ∙ 2² + 7∙ 2 - 40 = 3 ∙ 4 + 14 - 40 = 12 + 14 - 40 = -14
If area is negative, length or width must be negative.
It is impossible.
The area of a rectangle is given by the expression 3x^2+7x-40.
A. What is the length of the rectangle if its width is x+5?
B. If x=2cm, find the length, width and area of the rectangle?
1 answer