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3 years ago

15

Brenda went to the store 30 times last

1 answer:

Artist 52 [7]3 years ago

3 0

Answer:

7.5

Step-by-step explanation:

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A = 32°, a = 19, b = 14<br><br> solve the triangle using the law of cos

Lesechka [4]

Here is your solution.. hope it helps

6 0

2 years ago

Read 2 more answers

Two vectors A⃗ and B⃗ are at right angles to each other. The magnitude of A⃗ is 5.00. What should be the length of B⃗ so that th

creativ13 [48]

Answer:

Length of B is 7.4833

Step-by-step explanation:

The vector sum of A and B vectors in 2D is

$C=A+B=(a_1+b_1,a_2+b_2)$

And its magnitude is:

$C=\sqrt{(a_1+b_1)^2+(a_2+b_2)^2} =9$

Where

$a_1=Asinx$

$a_2=Acosx$

$b_1=Bsin(x+90)$

$b_2=Bcos(x+90)$

Using the properties of the sum of two angles in the sin and cosine:

$b_1=Bsin(x+90)=B(sinx*cos90+sin90*cosx)=Bcosx$

$b_2=Bcos(x+90)=B(cosx*cos90-sinx*sin90)=-Bsinx$

Sustituying in the magnitud of the sum

$C=\sqrt{(Asinx+Bcosx)^2+(Acosx-Bsinx)^2} =9$

$C=\sqrt{A^2sin^2x+2ABsinxcosx+B^2cos^2x+A^2cos^2x-2ABsinxcosx+B^2sin^2x} =9$

$C=\sqrt{A^2(sin^2x+cos^2x)+B^2(cos^2x+sin^2x)}$

$C=\sqrt{A^2+B^2} =9$

Solving for B

$A^2+B^2 =9^2$

$B^2 =9^2-A^2$

Sustituying the value of the magnitud of A

$B^2=81-5^2=81-25=56$

$B= 7. 4833$

8 0

3 years ago

The temperature inside a certain industrial machine at time t seconds after startup, for 0 < t < 10, is given by h(t) = 42

frutty [35]

Answer:

$t= \frac{125}{38} s$

Step-by-step explanation:

We are given the temperature inside the machine from startup until 10 seconds later, the formula is:

$h(t)= 42 \cdot t +1 - 4\cdot t +2 (degrees \, C)$

We want to know at what time t the temperature inside the machine will be equal to 128 °C.

So we set:

$h(t)=128$

$42\cdot t+1-4\cdot t+2=128$

Now, we rearrange the equation to keep terms with t on the left hand side and terms without t on the right hand side

$42\cdot t-4\cdot t=128-1-2$

and we simplify:

$(42-4)\cdot t= 128-2-1= 125$

$38 \cdot t = 125$

now it's easy to solve for t:

$t=\frac{125}{38}$

And thus we arrive to the solution.

5 0

3 years ago

A sheep is bought for £40 and sold for £33. What is the percentage loss?

valkas [14]

Answer:

£13 %11

Step-by-step explanation:

4 0

2 years ago

Three years ago, Sherman was twice as old as Clive. If Clive’s present age is c, which expression represents Sherman’s present a

Dahasolnce [82]

I belive it is S=2C. Even if it was three years ago, if Sherman was twice as old then, then he would be twice as old now. So you can get rid of the three years ago. if someone is twice as old, it is the same as doubling it.

3 0

2 years ago