The speed of light is approximately 1.86×10^5 miles per second.

-2x - 5y = 13 2x - 5y =17

Flura [38]

{-2x-5y=13

{2x-5y=17 (+)

-2x+2x-5y-5y=13+17

-10y=30 /:(-10)

y=-3

2x-5y=17

2x-5*(-3)=17

2x+15=17

2x=2

x=1

Solution: (1; -3)

6 0

3 years ago

Please Help!

alisha [4.7K]

Diagonal of the parallelogram divides the parallelogram in to two equal areas.

So area of parallelogram = 2(area of triangle)

According to the given diagram,

AB= 8, AD = 5 and BD = 11

So according to the Heron's formula,

Area of triangle = $\sqrt{s(s-a)(s-b)(s-c)}\\\\where,\\ s =\frac{a + b + c }{2}$

and a, b and c are the three sides of the triangle

Area of triangle ABD = $s=\frac{8 + 5 + 11}{2} \\\\s = \frac{24}{2}\\\\s = 12Area of triangle ABD = \sqrt{12(12 - 8) (12 - 5) (12 - 11)}\\\\Area of triangle ABD = \sqrt{12(4) (7) (1)}\\\\Area of triangle ABD = \sqrt{336}\\\\Area of triangle ABD = 18.33$

So, area of parallelogram ABCD = 2(area of triangle ABD)

area of parallelogram ABCD = 2 (18.33)

area of parallelogram ABCD = 36.66

area of parallelogram ABCD = 36.7 sq. units

6 0

3 years ago

Read 2 more answers

Shelly ran 2 1/4 miles Lynne ran 3 1/8 Miles WhobRan Farther and by how much

ValentinkaMS [17]

Lynne ran farther and by 7/8 miles

You can tell Lynne ran further because she ran 3 whole miles while shelly only ran 2 whole miles. Now you have to subtract to see how much Lynne had ran more.

You found a common denominator between 8 and 4. 4 can turn into 8. so you multiply 4x2 and 1x2 to get a mixed number of 2 2/8

Now you have to turn 3 1/8 because you cannot subtract 2/8 from 1/8. You can turn the fraction into 2 9/8 because there are 8 pieces in a whole.

2 9/8 - 2 2/8 = 0 7/8

Hope this helps! :)

6 0

3 years ago

The area of a rectangle is 980 in squared. the ratio of the length to the width is 5 : 4. find the length and the width.

ella [17]

Answer: The length of the rectangle is 35 in.

The width of the rectangle is 28 in.
_________________________________________________________
Explanation:
_________________________________________________________
The formula for the area, "A", of a rectangle:

Area (A) = length (L) * width (w) ;

that is: " A = L * w " ;

A = 980 in² (given);

ratio of the length to the width is: " 5 : 4 " (given);

→ Find the length (L) and the width (w).
_________________________________________________________

→ 980 in² = (5x) * (4x) ;

in which: " 980 in² " is the area of the triangle;

" 5x" = the length (L) of the rectangle, for which we shall solve;

" 4x" = the width (w) of the rectangle, for which we shall solve.
_______________________________________________________
If we find solve for "x" ; we can solve for "5x" and "4x" (the "length" and the "width", respectively); by plugging in the solved value for "x" ;
_______________________________________________________

→ 980 in² = (5x) * (4x) ;

↔ (5x) * (4x) = 980 in² ;

→ (5x) * (4x) = (5) * (4) * (x) * (x) = 20 * x² = 20x² ;

→ 20x² = 980 ;

Divide each side by "10" ; by canceling out a "0" on each side of the equation:

→ 2x² = 98 ;

Now, divide each side of the equation by "2" ;

→ 2x² / 2 = 98 / 2 ;

to get:

→ x² = 49 ;

Now, take the "positive square root" of each side of the equation; (since a "length or width" cannot be a "negative value") ;
to isolate "x" on one side of the equation; & to solve for "x" ;

→ ⁺√(x²) = √49 ;

to get:

→ x = 7 ;
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Now, we can solve for the "length" and the "width" ;

→ The length is: "5x" ;

5x = 5(7) = " 35 in " ;
______________________________________________________
→ The width is: "4x" ;

4x = 4(7) = "28 in."
______________________________________________________
Let us check our answer:

→ A = L * w ;

→ 980 in² = ? 35 in. * 28 in. ?? ;

Using a calculator: "35 * 28 = 980" . Yes! ;
____________________________________________________
{ Also note: " in * in = in² " ? Yes! } .
____________________________________________________

3 0

3 years ago

35% is 7 out of what number?

o-na [289]

Answer:

The number is 20.

Step-by-step explanation:

In this question, it is said that 35% of a number is equal to 7, then what is that number?

So, let the number be x.

Now, according to the question :

$\begin{gathered} \begin{array}{l} \quad{\dashrightarrow{\sf{35 \% \: of \: x = 7}}}\\\\\quad{\dashrightarrow{\sf{\dfrac{35}{100} \: of \: x = 7}}}\\\\\quad{\dashrightarrow{\sf{\dfrac{35}{100} \times x = 7}}}\\\\\quad{\dashrightarrow{\sf{\dfrac{35 \times x}{100} = 7}}}\\\\\quad{\dashrightarrow{\sf{\dfrac{35x}{100} = 7}}}\\\\\quad{\dashrightarrow{\sf{x = 7 \times \dfrac{100}{35}}}}\\\\\quad{\dashrightarrow{\sf{x =\dfrac{700}{35}}}}\\\\ \quad{\dashrightarrow{\sf{x = \cancel{\dfrac{700}{35}}}}}\\\\ \quad{\dashrightarrow{\sf{x =20}}}\\\\ \quad{\star{\underline{\boxed{\tt{\red{x =20}}}}}} \end{array}\end{gathered}$

Hence, the number is 20.

$\rule{300}{2.5}$

3 0

2 years ago

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