Length = 3w + 2 = 23.
Explanation:
Given :-
- The length of a rectangle is two more than three times the width = ( 3w + 2 )
- Let width of rectangle be w.
- Area of rectangle = 161.
Find :-
Solution :-
We know that ,
Area of rectangle = Length × Width.
161 = (3w + 2) × w
161 = 3w² + 2w
- Move constant to the left-hand side and change their signs.
0 = 3w² + 2w - 161
- Split the middle term- 2w as 23w - 21w.
0 = 3w² + 23w - 21w - 161.
- Factor out w from first pair and -7 from second pair.
0 = w ( 3w + 23 ) -7 ( 3w + 23)
0 = (3w + 23 ) ( w - 7)
- Using zero product property.
w - 7 = 0 , 3w + 23 = 0
w = 7 , w = -23/3
Since, width of rectangle can't be negative.
so, w = 7 is right value of width.
Calculate for Length.
length = 3w + 2 ( plug the value of width)
- length = 3 ( 7 ) + 2
- Length = 21 + 2
Hence, length = 23