How can you 24 with the numbers 6,6,2,1

When you reverse the digits in a certain 2 digit number you decrease its value by 81. What is the number if the sum of its digit

arlik [135]

Answer: 90 is a number which has 9 as the sum of its digits, 9+0=9 and if the digits are reversed, 09 is 81 less than 90.

Step-by-step explanation: Since the number must be a 2-digit number, it seems that 90 is the only number that qualifies.

If you need some equations, here is a way to set up a system to solve:

x+y= 9 rewrite to get a value for y to substitute:

y = 9-x

10x +y = 10y + x + 81 rewrite by moving (subtracting variable terms from both sides)

10x -x + y-10y = 81 combine like terms

9x - 9y = 81

Substitute for y and solve for x

9x - 9(9-x)= 81 distribute.

9x - 81 + 9x = 81

18x = 162. 162/18 = 9

x = 9

Substitute in the original equation to solve for y

9 + y = 9

y = 0

10(9) + 0 = 10(0) + 9 +81

90 - 81 = 09

6 0

3 years ago

What type of problems can always be solved using the law of cosines or sines?

laila [671]

Anytime you have a triangle (right triangles are preferred) where at least 2 angle measures and 1 side is known. Or, at least two sides and 1 angle measure.

OR..... 3 sides or three angles are known. So, sines or cosines could be used at almost anytime to find the sides and angles of a triangle!

4 0

3 years ago

The sum of the exterior angles of a convex polygon, one angle at each vertex, is equal to how many degrees?

alexdok [17]

The sum of the exterior angles of a polygon is always 360 degrees.
You have 6 sides. Each exterior angle must then be 360/60 = 60°

7 0

3 years ago

Can someone please give me the (Answers) to this? ... please ... I need help….

salantis [7]

Answer:

Step-by-step explanation:

1. x/64 = 36/x

x^2 = 2304

x=48

2. 9/x = x/25

x^2 = 225

x=15

3. x/16 = 9/x

x^2 = 144

x=12

4. 45/x = x/81

x^2 = 3645

x=27 $\sqrt{5}$

6 0

2 years ago

Find the quotient (line over 42 is repeating)

strojnjashka [21]

The correct answer is: [C]: " $\frac{21}{11}$ " .
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Explanation:
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Let us begin by converting the:
"0.42 (with the "repeating bar on the digits, "42") " ;

into a fraction, as follows:
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Let x = 0.42424242424242424242424242424242....

100x = 42.42424242424242424242424242424242....
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100x = 42.42424242424242424242424242424242....
– x = 0.42424242424242424242424242424242...
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99x = 42.000000000000000000000000000000.... ;

→ 99x = 42 ;

Divide each side of the equation by " 99 " ;
to isolate "x" on one side of the equation; & to solve for "x" ;
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→ 99x / 99 = 42/99 = (42 ÷ 3) / (99 ÷ 3) = 14/ 33;

→ x = " $\frac{14}{33}$ " .

So; "0.42 (with a repeating bar over the digits, "42" ;

is equal to: " $\frac{14}{33}$ "
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So, rewrite the question/problem being asked:
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"Find the quotient:
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$\frac{14}{33}$ ÷ $\frac{2}{9}$ ;

= $\frac{14}{33}$ * $\frac{9}{2}$ ;

Note: The "14" cancels to a "7" ; and the "2" cancels to a "1" ;
→ {since: " 14 ÷ 2 = 7 " ; and since: " 2 ÷ 2 = 1 "} ;

Note : The "33" cancels to an "11" ; and the "9" cancels to a "3" ;
 → {since: " 33 ÷ 3 = 11 " ; and since: " 9 ÷ 3 = 3 "} ;

And we can rewrite the problem as:
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" $\frac{7}{11}$ * $\frac{3}{1}$ " ;

= $\frac{(7*3)}{(11*1}$ = $\frac{21}{11}$ ;

→ which is: Answer choice: [C]: " $\frac{21}{11}$ " .
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3 0

4 years ago