So legnth is 7 more than 6 times width
l=7+6w
area=10 cm^2
lw=area
subsitute
7+6w for l
(7+6w)(w)=10
7w+6w^2=10
subtract 10 from both sides
6w^2+7w-10=0
factor
multiply 6 and -10
get -60
now find what 2 numbers multiply to get -60 and add to get 7
the answe ris -5 and 12
split up 7w into that
6w^2+7w-10=0
6w^2+12w-5w-10=0
group
(6w^2+12w)+(-5w-10)=0
undistribute factors
(6w)(w+2)+(-5)(w+2)=0
reverse distribute (ab+ac=a(b+c)
(w+2)((6w)+(-5))=0
(w+2)(6w-5)=0
set each to zero
w+2=0
subtract 2
w=-2
false, legnths cannot be negative
6w-5=0
add 5
6w=5
divide both sides by 6
w=5/6
subsitute
l=7+6w
l=7+6(5/6)
l=7+5
l=12
legnth=12 cm
width=5/6 cm
Answer: The answer is D
Step-by-step explanation: It is the only option that makes sense to me.
None of the answers are correct
a is 3 to the 1st power= 3
b is 3 to the 2nd power=9
c is 3 to the 4th power= 81
d is 3 to the 6th power= 729