Help. me. this makes no SENSE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! will give brainlyest

Someone please help me. I tried to solve it but couldn’t

Mariana [72]

Gradient = rise/run = -1/2
Thus:
y = -1/2x + c

Solve for c:
Pick a point for the values of y and x
(2,-2)

-2 = -1/2 (2) + c
c = -2 + 2
c = 0

Thus the equation is
y = -1/2x

4 0

3 years ago

Read 2 more answers

Jamal wants to install a rectangular 2025 cm² window in his garden shed. That area of window comes in several length/width combi

frosja888 [35]

Answer:

The ideal size will be a 45cmx45cm square, giving you a perimeter of 180cm.

Step-by-step explanation:

The shortcut answer here is that the square will always be the most efficient rectangle for border to area, so the sides should be the square root of 2025 cm, or 45 cm each, giving you a total of 180 minimum perimeter.

The full solution is to express the perimeter as a function of the length and width, define either length or width as a function of the other, take the entire expression's derivative and solve for zero. Let's do it:

So first the area:

2025 = wl

l = 2025 / w

Now the sides:

$p = 2w + 2l\\p = 2w + 2(2025 / w)\\p = 2w + 4050 / w$

Then we can take its derivative with respect to w

$p = 2w + 4050\frac{1}{w}\\\frac{dp}{dw} = 2 + 4050\frac{-1}{w^2}\\$

Now we can set the derivative to zero, and solve for w:

$\frac{dp}{dw} = 2 + 4050\frac{-1}{w^2}\\0 = 2 + \frac{-4050}{w^2}\\-2 = \frac{-4050}{w^2}\\2w^2 = 4050\\w^2 = 2025\\w = \sqrt{2025}\\w = 45$

So the width being 45, we can get the length by dividing the area by that amount, which of course is also 45.

3 0

3 years ago

A tree that grows 3 feet every 5 years is growing at a rate of year. feet per

jenyasd209 [6]

Answer:

A.0.6

0.6*5yrs=3feet a year

Step-by-step explanation:

8 0

3 years ago

A school has 360 students. 4/9 of them are girls. 3/5 of them are girls below the age of ten. How many girls are in the school a

quester [9]

To find total number of girls multiply total students by the fraction of girls:

360 x 4/9 = 360 x 4 = 1440/9 = 160 total girls.

If 3/5 are below the age of ten, that means 2/5 are above the age of ten.

Multiply the total number of girls by 2/5:

160 x 2/5 = 320/5 = 64

There are 64 girls above the age of ten.

4 0

3 years ago

Answer this fast will mark brainlist for sure answer the question whichever u know :)

Kay [80]

Answer:

$\large\boxed{1.\ 38\ and\ 22}\\\boxed{1'.\ 42\ and\ 30}$

Step-by-step explanation:

$1.\\x,\ y-the\ numbers\ (x>y)\\\\\text{We have the system of equations:}\\\\\underline{\left\{\begin{array}{ccc}x-y=16\\x+y=60\end{array}\right}\qquad\text{add both sides of the equations}\\.\qquad2x=76\qquad\text{divide both sides by 2}\\.\qquad\boxed{x=38}\\\\\text{Put the value of x to the second equation.}\\\\38+y=60\qquad\text{subtract 38 from both sides}\\\boxed{y=22}$

$1'.\\x-larger\ part\\x-12-smaller\ page\\\\x+(x-12)=72\\x+x-12=72\qquad\text{add 12 to both sides}\\2x=84\qquad\text{divide both sides by 2}\\\boxed{x=42}\\\boxed{x-12=30}$

6 0

3 years ago