Answer:
Step-by-step explanation:
Formula
A = L * W
Givens
W = W
L = W + 2
Solution
Area = L*W
Area = (W+2)*W = 80 Remove the brackets.
Area = W^2 + 2W = 80 Subtract 80 from both sides.
Area = w^2+2W-80=80-80 Combine
Area = w^2 +2W-80 = 0 Factor.
Area = (w+10)(w - 8) = 0
W + 10 = 0 won't work
W = - 10 which isn't possible
W- 8 = 0
W = 8
L = 8 + 2 = 10
The answer looks like A
Answer:
60
Step-by-step explanation:
straight line =180
180-120=60
Answer: a. 19
Step-by-step explanation:
it only has 1 and itself
D=number of dogs
c=cats
d equals 4 less than 2 times c
d=-4+2c
20 dogs
d=20
subsitute
20=-4+2c
add 4
24=2c
divide 2
12=c
12 cats
Answer:
8m ×3.5m
Step-by-step explanation:
Area of rectangle= length ×width
Let the length and width of the rectangle be L and W meters respectively.
Area of rectangle= LW
LW= 28 -----(1)
L= 2W +1 -----(2)
Subst. (2) into (1):
(2W +1)(W)= 28
<em>Expand:</em>
2W² +W= 28
<em>-28 on both sides:</em>
2W² +W -28= 0
<em>Factorise</em><em>:</em>
(W +4)(2W -7)= 0
W +4=0 or 2W -7=0
W= -4 (reject) or W= 3.5
Substitute W= 3.5 into (2):
L= 2(3.5) +1
L= 7 +1
L= 8
∴ The dimensions of the rectangle is 8m ×3.5m.
