The product of 12 and y increased by 11

the length of a rectangle is 7 yd less than three times the width, and the area of the rectangle is 66 yd(squared). find the dim

Alex_Xolod [135]

So legnt=l
width=w
l=-7+3w
l=3w-7

area=66
area=legnth times width or
area=lw

subisutte
area=lw
l=3w-7
66=(3w-7)(w)
66=3w^2-7w
subtrac 66 from both sides
0=3w^2-7w-66
factor
HOW TO
multiply 3 and -66=-198
find what 2 numbers add up to -7 and multiply to get -198
the numbers area 11 and -18
so
3w^2-18w+11w-66=0
factor
(3w^2-18w)+(11w-66)=0
(3w)(w-6)+(11)(w-6)=0
factor using distributive (ab+ac=a(b+c))

(3w+11)(w-6)=0
set them to zero
3w+11=0
subtract 11
3w=-11
legnths cannot be negative so we discard this

w-6=0
add 6
w=6

width=6
legnth=3w-7
length=3(6)-7
legnt=18-7
legnth=11

width=6
legnth=11

7 0

3 years ago

8th grade math . Pythagorran practice <br>

Serhud [2]

The answers according to rows are:

ROW 1 : diameter of base = 10, base area = 25π, volume of cylinder = 175π volume of cone = $\frac{175}{3}$ π

ROW 2 : base radius = 3, base area = 9π, height = 40/3, volume of cylinder = 120π
ROW 3 : base radius = 6, base diameter = 12, height = 4, volume of cylinder = 144π

<h3>What is mensuration?</h3>

Mensuration is an aspect of geometry that deals with measurement of volumes and area.

Analysis:

Row 1

Diameter of base = 2 x radius = 2 x 5 = 10

Base area = π $r^{2}$ = π $(5)^{2}$ = 25 $\pi$

Volume of cylinder = base area x height = 25π x 7 = 175π

Volume of cone = 1/3 x volume of cylinder = 175π/3

Row 2

Base radius = base diameter/2 = 6/2 = 3

Base area = π $r^{2}$ = π $(3)^{2}$ = 9π

Volume of cone = 1/3 x base area x height

base area x height = 3 x volume of cone

base area x height = 3 x 40π

Height = 120π/9π = 40/3

Cylinder volume = 3 x cone volume = 3 x 40π = 120π

Row 3

Base area = π $r^{2}$

36π = π $r^{2}$

r2 = $\sqrt{36}$

r = 6

Base diameter = 2 x 6 = 12

Volume of cone = 1/3 x base area x height

48π = 1/3 x 36π x height

Height = 4

Cylinder volume = 3 x 48 = 144π

In conclusion,

ROW 1 : diameter of base = 10, base area = 25π, volume of cylinder = 175π

volume of cone = $\frac{175}{3}$ π

ROW 2 : base radius = 3, base area = 9π, height = 40/3, volume of cylinder = 120π

ROW 3 : base radius = 6, base diameter = 12, height = 4, volume of cylinder = 144π

Learn more about mensuration: brainly.com/question/18541562

#SPJ1

4 0

2 years ago

Victoria bought a jacket in the sale which had 20% off. If it cost ?36 on sale what did it cost before the sale?

Basile [38]

Answer:

The jacket costs $45

Step-by-step explanation:

In order to find this, notice that the price of the sale represents 80% of the total cost. This is because we took 20% away with the sale. Now we can find the overall amount by dividing the sale cost by the amount it represents.

$36 / 80% = $45

7 0

3 years ago

You order 10 large aspen trees from a nursery. They will deliver them to you at a cost of $25 for the first tree plus $5 for eve

natka813 [3]

Answer:

D. $70

Step-by-step explanation:

you can first think that the first tree is $25 plus the nine trees for 5 dollars so

5x9=45

45+25=70

Hope this helps :D

3 0

2 years ago

The following is a rhombus, solve for x

lorasvet [3.4K]

Answer:

maybe since the rhombus is divided into triangles it'll be easier. x = 8

Step-by-step explanation:

the total degrees in a triangle would be 180 and the inner little angles would be 90 degrees so you would solve for (7x - 1) + (4x + 3) + 90 = 180 so 11x + 2 = 90 so 11x = 88 so x = 8

hope this helps!

7 0

2 years ago