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3 years ago

Explain how you used mental math

Mathematics

2 answers:

andriy [413]3 years ago

4 0

Addition, I would use the principles of addition.

DIA [1.3K]3 years ago

4 0

Addition is the correct answer

You might be interested in

Solve this equation:<br><br> |x-2|=6x+18

sineoko [7]

X-2=6x+18
-x -x
-2=5x+18
-18 -18
-20=5x
x=-4

5 0

3 years ago

Moreira is comparing prices at two video game rental companies rebound game rental charges a base fee of four dollars and an add

uysha [10]

Answer:

Number of days = 3

Step-by-step explanation:

Let

x = number of days

Rebound game rental = 4 + 2x

Girl right game center = 1 + 3x

Equate both rental companies to find x

Rebound game rental = Girl right game center

4 + 2x = 1 + 3x

Collect like terms

4 - 1 = 3x - 2x

3 = x

x = 3 days

Number of days = 3

5 0

3 years ago

NO LINKS OR ANSWERING QUESTIONS YOU DON'T KNOW!!! THIS IS NOT A TEST OR AN ASSESSMENT!! Please help me with these math questions

Art [367]

Answer:

See below

Step-by-step explanation:

3. What are two ways that a vector can be represented?

Considering a vector $\vec{v}$ in some vector space $\mathbb R^n$ we have

$\vec{v} = \langle a,b\rangle$

This is the component form. I don't like that way. It is probably used in high school, but

$\vec{v} = \begin{pmatrix} a\\ b\\ \end{pmatrix}$

is preferable because the inner product on $\mathbb R^n$ is defined to be

$\langle a,b\rangle := \sum_{i = 1}^n a_i b_i$

You can also write it using linear form such as $\vec{v} = 2i+2j$

For this question, I think you meant

vectors

$\vec{u_1} = (-8, 12)$

$\vec{u_2} = (13, 15)$

Once

$\cos(\theta)=\dfrac{\vec{u_1} \cdot\vec{u_2}}{||\vec{u_1}||||\vec{u_2}||}$

Considering that the dot product is

$\vec{u_1}\cdot \vec{u_2} = (-8)\cdot 13 + 12\cdot 15 = -104+180= 76$

and the norm of $\vec{u_1}$ is $||\vec{u_1}|| = \sqrt{(-8)^2 + 12^2} = \sqrt{64 + 144}= \sqrt{208}$

and the norm of $\vec{u_2}$ is $||\vec{u_2}|| = \sqrt{13^2 + 15^2} = \sqrt{169 + 225}= \sqrt{394}$

Thus,

$\cos(\theta)=\dfrac{76}{\sqrt{208} \sqrt{394}} = \dfrac{19}{\sqrt{13}\sqrt{394}}=\dfrac{19}{\sqrt{5122}}$

$\therefore \theta = \arccos \left(\dfrac{19}{\sqrt{5122}} \right)$

3 0

3 years ago

How do i do this? and what’s the answer?

Trava [24]

This is a parallelogram, and the answer is 8.04

8 0

3 years ago

Please help. 10 points. Please do not guess. Guesses will be reported. Thanks

Allushta [10]

The intersecting secant-tangent theorem says that

$AP^2=PT\cdot TO$

where T is the point at which line segment PO touches the circle. Similarly,

$BP^2=PT\cdot TO$

so we have

$AP^2=BP^2\implies AP=BP$

OP is of course as long as itself, and AO and BO are radii of the same circle so they have the same lengths.

This means triangles APO and BPO are congruent, which means angles APO and BPO are congruent, so angle APB is bisected by PO.

8 0

3 years ago