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4 years ago

If 40% of a number is 56 what was the original number

1 answer:

7 0

$\begin{array}{ccc}100\%&-&x\\40\%&-56\end{array}\ \ \ |cross\ multiply\\\\40x=56\times100\\40x=5600\ \ \ \ \ |divide\ both\ sides\ by\ 40\\\\\boxed{x=140}$

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Find the points of intersection of the following function graphs: y=20x−70 and y=70x+30

LekaFEV [45]

Answer:

(-2,-110)

Step-by-step explanation:

First solve for x

20x−70=70x+30

x= -2

Now substitute x for -2

y=20x−70

y=20(-2)-70

y = -110

4 0

4 years ago

Solve the equation for exact solutions over the interval [0, 2π).

quester [9]

Answer:

$\displaystyle x=\left\{0, \frac{2\pi}{3}, \frac{4\pi}{3}\right\}$

Step-by-step explanation:

We want to solve the equation:

$-2\cos^2(x)=-\cos(x)-1$

Over the interval [0, 2π).

First, notice that this is in quadratic form. So, to make things simpler, we can let <em>u</em> = cos(x). Substitute:

$-2u^2=-u-1$

Rearrange:

$2u^2-u-1=0$

Factor:

$(2u+1)(u-1)=0$

Zero Product Property:

$2u+1=0\text{ or } u-1=0$

Solve for each case:

$\displaystyle u=-\frac{1}{2}\text{ or } u=1$

Back-substitute:

$\displaystyle \cos(x)=-\frac{1}{2}\text{ or } \cos(x)=1$

Using the unit circle:

$\displaystyle x=\left\{0, \frac{2\pi}{3}, \frac{4\pi}{3}\right\}$

7 0

3 years ago

GUYS PLEASE HELP ME PLEASE HELP HELP PLEASE HELP ASAP GUYS HELP!!!!!

slega [8]

Answer:

$SA=5\ yd^2$

Step-by-step explanation:

we know that

The surface area of the square pyramid is equal to the area of the square base plus the area of its four triangular faces

$SA=b^2+4[\frac{1}{2}(b)(h)]$

we have

$b=1\ yd\\h=2\ yd$

substitute

$SA=1^2+4[\frac{1}{2}(1)(2)]$

$SA=5\ yd^2$

5 0

3 years ago

3. Rectangle DEFG was rotated on the coordinate plane.

lesantik [10]

^they suck , but the answer is B <3

4 0

3 years ago

What is the value of A when we rewrite 4^31x as A^x

Brut [27]

Answer:

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers