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STatiana [176]
3 years ago
7

2) 3x + 4y = 8 2x+y=42 a) (30, -19) b) (31, -20) c) (32,-22) What is the answer

Mathematics
1 answer:
kirza4 [7]3 years ago
7 0

Answer:

C

Step-by-step explanation:

We can solve simultaneous equations using substitution method, elimination method or graphical method. But for this purpose, we will be using the elimination method.

3x+4y=8 Equation 1

2x+y=42 Equation 2

Multiply Equation 1 by 2 and equation 2 by 3, so as to get the same coefficient for x

2(3x+4y=8)= 6x+8y=16 Equation 3

3(2x+y=42)= 6x+3y=126 Equation 4

Subtract equation 4 from 3, to eliminate x

6x-6x=0

8y-3y= 5y

16-126= -110

We now have 5y=-110

Divide both sides by 5,

y= -110/5

= -22

Substituting for y in equation 2

2x+(-22)= 42

2x= 42+22

2x=64

x= 64/2

= 32

(x, y)

(32, -22)

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Subtract 3.65X from each side:

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3 years ago
-45 / -5 = <br> plz can you help me
garri49 [273]
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IceJOKER [234]

Answer: 85.104

Step-by-step explanation: Adding decimals is something you will use a lot. Take the time to learn it now. So when you are adding decimals there are some important things to keep in mind. 1. Line the decimals up. Let me explain. Lets do a example. Lets say its 14.5+ 15.74. The first thing you would need to do is line them up like this-->

14.5

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After you do that, Do you see a black space next to the 14.5? When adding decimals this is a big nono. So what you can do is add a 0. Adding a zero is only applicable when you have one number that has 1 more number(its my best way to explain it).( so like you would add a zero if your equation was like 23.5 +18.99. but you wouldn't do it if it was 17.5+19.4).  Example equation should look like this:

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Step 2. Put the decimal down to where it lines up. Like this:

 14.5 0

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     .<------ make sure it lines up!

Step 3. Add regularly. Just ignore the decimal in the equation and just add. The answer would be 30.24. If you don't know how to add, I don't think your old enough for a brainly account:)

Step 4. Remove the zero. Zero as a number means nothing. So its ok in math to add a zero at the end of a decimal. So 4.0 is the same as 4 or 4.0000000000000. So when you have another problem, and your answer is something like 95.320, you can just remove the zero. So it would be 95.32:)

Hope I Helped! (this took me a long time to type out)

:)

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