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o-na [289]
3 years ago
5

Please help! provide thorough explanation and use elimination method!!

Mathematics
1 answer:
ICE Princess25 [194]3 years ago
8 0

Multiply both sides of the second equation by 100 to get rid of the decimals:

0.05<em>n</em> + 0.10<em>d</em> = 1.50

==>  5<em>n</em> + 10<em>d</em> = 150

Multiply both sides of the first equation by -5:

<em>n</em> + <em>d</em> = 21

==>  -5<em>n</em> - 5<em>d</em> = -105

Add the two equations together:

(5<em>n</em> + 10<em>d</em>) + (-5<em>n</em> - 5<em>d</em>) = 150 + (-105)

Notice that the terms containing <em>n</em> get eliminated and we can solve for <em>d</em> :

(5<em>n</em> - 5<em>n</em>) + (10<em>d</em> - 5<em>d</em>) = 150 - 105

5<em>d</em> = 45

<em>d</em> = 45/5 = 9

Plug this into either original equation to solve for <em>n</em>. Doing this with the first equation is easiest:

<em>n</em> + 9 = 21

<em>n</em> = 21 - 9 = 12

So Donna used 12 nickels and 9 dimes.

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In ΔDEF,{EF}\cong{DE} EF ≅ DE and m∠E = 104°. Find m∠D.
Alexeev081 [22]

The 3 inside angles need to equal 180.

Subtract E from 180 to find the sum of the other two angles:

180 - 104 = 76

Now because EF ≅ DE , angle D and F would be the same so divide 76 by 2

Angle D = 38

7 0
3 years ago
Ryan bought a digital camera with a list price of $150 from an online store offering a 5% discount. He needs to pay $5.50 for sh
zhannawk [14.2K]
I am thinking 150-5% = 142.50 + 5.50 = $148
3 0
3 years ago
−5.5x + 0.46 = −3.94
aliina [53]

Answer:

x= 0.78 (rounded to the hundredth)

Step-by-step explanation:

-5.5x + 0.46 = -3.94

You need to isolate x so the easiest thing to do is subtract 0.46 and move it to the other side of the equal sign.

-5.5x= -3.84 - 0.46

-5.5x = -4.3

divide -5.5 to get x alone

x= -4.3/-5.5

x= 0.78

7 0
3 years ago
9) Solve by the elimination method.<br><br> x + y = -5<br> x - y = 11
vlabodo [156]
<h2><u>Answer:</u></h2>

x = 3

y = -8

<h2><u>Step-by-step explanation:</u></h2>

x + y = -5

x - y = 11

Since the y's will cancel out, we don't need to modify the two equations in any way.

Now, just add the two equations.

x + x = 2x

y + (-y) = 0

-5 + 11 = 6

2x = 6

Divide by 2.

x = 3

To find y, plug 3 in as "x" in one of the two equations.

3 + y = -5

y = -8

6 0
3 years ago
4, 8, 12, 16, 20 24, 36, 40 44 48 52 56 60 64 68 72 76 80 84 88 92 96 100... Those are the multiples of 4. Now find out which ar
Lilit [14]

Answer:

Ok the answer of 6 are  12, 18, 24, 30, 36, 42, and 48. The multiples of 9 are 18,27,36,45,54,63,72,81,90,99,108,117,126,135,144,153,162,171,180,189,198,. Hope it helps!

7 0
3 years ago
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