SOLUTION: The width of a rectangle is 5 less than twice its length. If the area of the rectangle is 70 cm2, what is the length of the diagonal?
Algebra ->
Human-and-algebraic-language
-> SOLUTION: The width of a rectangle is 5 less than twice its length. If the area of the rectangle is 70 cm2, what is the length of the diagonal?
Log On
Question 1047288: The width of a rectangle is 5 less than twice its length. If the area of the rectangle is 70 cm2, what is the length of the diagonal?
You can put this solution on YOUR website! The diagonal will be the hypotenuse of a right triangle where the legs are one length and one width.
length=L
width=(2L-5)
Area is their product or 2L^2-5L=70
2L^2-5L-70
L=(1/4)*5+/-sqrt (25+560); sqrt 585=24.19
L=(1/4)*(29.19), use only positive root
L=7.30 cm
Width=14.60-5=9.60
Their product is 70.08, within rounding. If I use 7.2967 and 9.5934, I get 70.0002
The sqrt of the hypotenuse = sqrt of sum of 7.3^2 and 9.6^2
That equals sqrt (145.45)=12.06 cm
