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2 years ago

The length of the base of an isosceles triangle is x. The length of a leg is 3x-5. The perimeter of the triangle is 39. Find X.

Mathematics

1 answer:

frozen [14]2 years ago

5 0

Answer:

x = 7

Step-by-step explanation:

In an isosceles triangle, both legs are always congruent. The length of one leg is given, and the other leg has to be the same. The perimeter of this triangle can be written as:

$x+(3x-5)+(3x-5)=39$

With this equation, all you need to do is solve for x.

$3+3x-5+3x-5=39\\(-5-5)+(x+3x+3x)=39\\-10+7x=39\\7x=49\\x=7$

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In this figure, the distance from a to b is 10 units. what else is true

Aneli [31]

Need something to go off of and the choices.

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2 years ago

A, B, C and D are four towns.

djverab [1.8K]

Three of the four towns are on the vertices of the triangle ΔCBD, through

which the bearing can calculated.

<h3>Response:</h3>

The bearing of D from B is approximately <u>209.05°</u>

<h3>Method by which the bearing is found;</h3>

From the given information, we have;

AC = AB = 25 km

∠BAC = 90° (definition of angle between north and east)

ΔABC = An isosceles right triangle (definition)

∠ACD = ∠ABC = 45° (base angles of an isosceles right triangle)

$tan(\angle ABD) = \dfrac{45}{25}$

$\angle ABD = arctan \left(\dfrac{45}{25} \right) \approx 60.945^{\circ}$

The bearing of <em>D</em> from <em>B</em> is the angle measured from the north of <em>B</em> to the

direction of <em>D.</em>

<em />

Therefore;

The bearing of D from B ≈ 90° + (180° - 60.945°) = <u>209.05°</u>

Learn more about bearings in mathematics here:

brainly.com/question/10710413

5 0

2 years ago

Does anyone know the answer?

GREYUIT [131]

Answer:

Step-by-step explanation:

8 0

1 year ago

Read 2 more answers

If a=i+7j+k and b=i+11j+k, find a unit vector with positive first coordinate orthogonal to both a and

Scilla [17]

Take the cross product, then normalize the result.

$\mathbf a\times\mathbf b=\begin{vmatrix}\mathbf i&\mathbf j&\mathbf k\\1&7&1\\1&11&1\end{vmatrix}=-4\,\mathbf i+4\,\mathbf k$

This has norm

$\|\mathbf a\times\mathbf b\|=\sqrt{(-4)^2+4^2}=4\sqrt2$

and so a unit vector orthogonal to both given vectors is

$\dfrac{\mathbf a\times\mathbf b}{\|\mathbf a\times\mathbf b\|}=-\dfrac1{\sqrt2}\,\mathbf i+\dfrac1{\sqrt2}\,\mathbf k$

An equally correct answer would be the negative of this vector, since $\mathbf b\times\mathbf a=-\mathbf a\times\mathbf b$ .

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2 years ago

Annie needs $30 to buy a coat she has saved $12 and plans to work as a baby siter to earn $6 per hour which inequality shows the

tekilochka [14]

Answer:

The answer would be B. 12 + 6n is greater than or equal to 30, so n is less than or equal to 3.

explanation:

I'm bad with explaining things, but I'll try my best to explain why this is the right answer.

12 + 6n ≥ 30, so n ≤ 3

let's start with the 12 at the beginning of the inequality, Annie already has $12, so the 12 in the inequality shows the amount of money she already has being added to the $6 per hour of babysitting she needs to do (n).

Now for the + 6n, the plus is there to show that the $12 Annie already has is being added to the 6n. The 6n then represents the $6 Annie makes each hour and the n represents how many hours she needs to babysit in order to get $30. The 6 is being multiplied by the amount of hours she needs to babysit to show how much money Annie would make. Then you add on the $12 she already has.

Annie then needs at least $30, but if she makes more than $30 then she will simply have more money than needed, therefore you use the greater than or equal to sign to show that she can have more money than just $30 after working.

I hope this helps, and sorry if my explanation is hard to understand lol.

6 0

2 years ago