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3 years ago

Twice the difference of a number + -3 is 4 find the number

Mathematics

1 answer:

NNADVOKAT [17]3 years ago

7 0

Answer:

The number is 5

Step-by-step explanation:

If we need to find the hidden number, Which for simplicity's sake we will denote as "n", lets first write out the equation.

"2 x [n + (-3)] = 4"

We can work through this problem backwards. if we need two times the sum of "n" and (-3) to get to 4, the only number that can be multiplied by 2 to get a product of 4 is 2, so "n" + (-3) must equal 2. so, From here, we can figure out that since 5 + (-3) equals 2, "n" Must equal 5. so, if we plug in 5 for "n" the equation looks like this:

"2 x [5 + (-3)] = 4"

So, since the equation makes sense, the answer is, "n = 5"

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The radius of a circle is (x-3)m. find the area of the circle

Flura [38]

Answer:

πx² -6πx + 9π

π(x² - 6x + 9)

Step-by-step explanation:

area = πr² = π(x-3)² = π(x² - 6x + 9) = πx² - 6πx + 9π

8 0

3 years ago

Claire purchases a new dress for the prom. The dress is priced $160, but it is on sale for 30% off. Claire’s aunt works at the s

djverab [1.8K]

Answer:

$Total = \$103.20$

Step-by-step explanation:

Given

$Amount =\$160$

$D_1 = 30\%$ --- first discount

$D_2 = 10\%$ --- second discount

$Sales\ Tax = 7.5\%$

Required

Determine the amount paid

First, we add the total discount:

$D = D_1 + D_2$

$D = 30\% + 10\%$

$D = 40\%$

If she got a discount of 40%, then she paid 60% (i.e. 100% - 40%)

So:

$Amount = 60\% * \$160$

$Amount = \$96$

Calculate the sales tax

$Sales\ Tax = 7.5\% * \$96$

$Sales\ Tax = \$7.2$

$Total = \$96 + \$7.2$

$Total = \$103.20$

3 0

3 years ago

A swimming pool has to be drained for maintenance. The pool is shaped like a cylinder with a diameter of 5 m and a depth of 1.4

Korolek [52]

Answer:

8 hours

Step-by-step explanation:

basic equation

Q (flow rate) = V (volume)/ t (time)

so to find the time we just rearrange the equation and become

t = V/Q

V of cylinder

V = πr²T

and r (radius) = ½ diameter

V = 3.14 x 5² x 1.4

V = 109.9 m³

if the Q is 13 m³/hour then

t = 109.9/13 = 8.453 hours

round to nearest hour = 8 hours

6 0

3 years ago

If you could show the steps that would be great

zvonat [6]

Answer:

24x + 8

Step-by-step explanation:

4 + 16 - 12(1 + 2x)

Solve

Show steps

__________________

We have a dilemma here, there is a variable and constant numbers in this equation. No fear, this is when like terms comes into play, where you can only combine two numbers that have the same ending, whether it be variables, exponents, e.t.c.

Distribute :

4 + 16 - 12(1 + 2x)

4 + 16 - (12(1) + 12(2x))

4 + 16 - 12 + 24x

Use PEMDAS (Add left to right) :

4 + 16 - 12 + 24x

20 - 12 + 24x

8 + 24x

24x + 8

4 0

3 years ago

Read 2 more answers

In ΔJKL, k = 9.6 cm, l = 2.7 cm and ∠J=43°. Find ∠L, to the nearest 10th of a degree.

Bogdan [553]

Answer:

L = 10.64°

Step-by-step explanation:

From the given information:

In triangle JKL;

line k = 9.6 cm

line l = 2.7 cm; &

angle J = 43°

we are to find angle L = ???

We can use the sine rule to determine angle L:

i.e

$\dfrac{j}{SIn \ J} = \dfrac{l}{ SIn \ L}$

Using Pythagoras rule to find j

i,e

j² = k² + l²

j² = 9.6²+ 2.7²

j² = 92.16 + 7.29

j² = 99.45

$j = \sqrt{99.45}$

j = 9.97

∴

$\dfrac{9.97}{Sin \ 43} = \dfrac{2.7}{ Sin \ L}$

${9.97 \times Sin (L ) = (2.7 \times Sin \ 43)$

$= Sin \ L = \dfrac{ (2.7 \times Sin \ 43)}{9.97 } \\ \\ = Sin \ L = \dfrac{ (2.7 \times 0.6819)}{9.97 } \\ \\ = Sin \ L = 0.18466 \\ \\ L = Sin^{-1} (0.18466) \\ \\ L = 10.64 ^0$

3 0

3 years ago