Answer:
See below
Step-by-step explanation:
<u>Sides of the garden</u>
<u>New dimensions of the garden</u>
<u>1. The area of the new garden</u>
- (16 + 2x)(8 + x) =
- 2x^2 + 32x + 128
<u>2. The difference in area </u>
- 2x^2 + 32x + 128 - 16*8 =
- 2x^2 + 32x
<u>3. x= 2 effect on the area</u>
- 2*2^2 + 32*2 =
- 8 + 64 =
- 72 ft²
<u>4. Area difference = 160</u>
- 2x^2 + 32x = 160
- x^2 + 16x - 80 = 0
- Solving we get positive root of 4 ft
<u>5. Area difference = 4 times</u>
- 2x^2 + 32x = 128*3
- 2x^2 + 32x - 384 = 0
- x^2 + 16x - 192= 0
- Solving we get positive root of 8 ft
Because it specialises the groups that go into the number.
The volume of the candle initially is:
V=Ab*h
Area of the base of the cylinder: Ab=pi*r^2
pi=3.14
Radius of the base: r=4 cm
Height of the cylinder: h=6 cm
Ab=pi*r^2
Ab=3.14*(4 cm)^2
Ab=3.14*(16 cm^2)
Ab=50.24 cm^2
V=Ab*h
V=(50.24 cm^2)*(6 cm)
V=301.44 cm^3
The candle melts at a constant rate of:
r=(60 cm^3)/(2 hours)=(120 cm^3)/(4 hours)=(180 cm^3)/(6 hours)
r=30 cm^3/hour
The amount of candle melted off after 7 hours is:
A=(30 cm^3/hour)*(7 hours)
A=210 cm^3
The percent of candle that is melted off after 7 hours is:
P=(A/V)*100%
P=[(210 cm^3)/(301.44 cm^3)]*100%
P=(0.696656051)*100%
P=69.66560510%
Rounded to the nearest percent
P=70%
Answer: 70%
15. -2
16. A. The pool was originally empty