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3 years ago

Plz help me I don’t understand this

Mathematics

2 answers:

Helga [31]3 years ago

4 0

We need to solve the problem by algebra which is taught in most schools.

In algebra, most of the time, we call the number we're looking for as "x", which we don't know yet. Using "x", we formulate an equation according to what is given, which is O has 32 stamps, and S has 154.

When each of them bought x stamps, O has 32+x, and S has 154+x.

We're also told that S now has 3 times as many as O, so the equation goes

154+x = 3(32+x) .......(1) from which x can be solved.

We first expand both sides.

154+x = 96+3x (called the distribution property)

Now subtract x from each side,

154+x-x=96+3x-x => 154 = 96+2x

Now subtract 96 from each side, and simplify as above

154-96 = 2x

simplify again

58=2x

divide by two on each side,

x=29.

Let's check: 3*(32+29)=3*(61)=183 = 154+29, so the answer is correct.

Since they bought EACH 29 stamps, the bought a total of 2*29=58 stamps (which happens to be the difference of number of stamps at the beginning).

hram777 [196]3 years ago

3 0

493 Stan for all buy

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4 years ago

Let r3 have the euclidean inner product. let u = (-1, 1, 1) and v = (-7, 6, 15). if ||ku + v||= 7, what is k? give the exact ans

amm1812

Ma $k\mathbf u+\mathbf v=k(-1,1,1)+(-7,6,15)=(-k-7,k+6,k+15)$

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3 years ago

Write an equation in standard form of the line passing through the points (12, 3) and (-3, 8).

aliya0001 [1]

Answer:

x + 3y = 21

Step-by-step explanation:

$(x_{1},y_{1})=(12,3) \\\\(x_{2},y_{2})=(-3,8)\\\\Slope= \dfrac{y_{2}-y_{1}}{x_{2}-x_{1}}\\\\= \dfrac{8-3}{-3-12}= \dfrac{5}{-15}\\\\= \dfrac{-1}{3}$

Equation of the line: y =mx+ b

$y = \dfrac{-1}{3}x+b\\\\\\Plugin \ x = 12 \ and \ y=3 \ in \ the \ above \ equation\\\\3= \dfrac{-1}{3}*12+b\\\\3= -4+b\\\\3+4 = b\\\\b = 7\\\\\\\y= \dfrac{-1}{3}x+7\\\\$

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3 years ago

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eimsori [14]

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3 years ago

Find the area of the shape, show work pls ill give brainiest

andre [41]

Answer:

6.2

Step-by-step explanation:

Although there's multiple ways to solve this problem, my method will be to simply find the area for the full triangle (the empty + orange triangles) and subtract the area of the smaller, empty triangle.

Now, you that area for a triangle is 1/2*base*height.

To find the measurements for the full triangle, you must add up the bases for the two smaller triangles:

$Base_{total} = Base_{empty} + Base_{orange} \\Base_{total} = 1.9ft + 3.1 ft\\Base_{total} = 5 ft$

Height is the same for both triangles so Height total = 4 ft.

Now the total area can be calculated:

Area total= 1/2* base_total * height_total

Area total = 1/2 * 5ft * 4 ft

Area total = 20 / 2 = 10 ft squared

Lastly, subtract the area of the empty triangle from the total triangle to find the orange triangle.

Area Empty Triangle = 1/2 * base_empty * height_empty

Area Empty Triangle = 1/2 * 1.9ft * 4 ft = 7.6 ft / 2 = 3.8 ft squared

Area total - Area empty = 10ft^2 - 3.8ft^2 = 6.2 ft squared

8 0

3 years ago