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4 years ago

Solve each system by substitution: 3x+y=2 4x+y=20 How do I solve this and set this up

Mathematics

2 answers:

Sholpan [36]4 years ago

8 0

Solve the first equation for y.

3x+y=2

y=2-3x

Substitute

4x+(2-3x)=20

4x+2-3x=20

x=18

MissTica4 years ago

7 0

So you want to isolate one of the variables in one of the equations. Using the first equation, we can make 3x+y=2 y=2-3x.
Then plug y=2-3x into the second equation:
4x+(2-3x)=20
Then solve.
x+2=20
x=18
Finally, plug the x value back into any of the two equations to find y. This is essential to get full credit!
4(18)+y=20
72+y=20
y= -52

x=18
y= -52

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liberstina [14]

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3 years ago

Can somebody plz help answer these last questions correctly (only if u know how to do this) if u can answer the because ones too

natima [27]

Answer:

∠e = 105° because ∠e and the 105° angle are vertically opposite angles

∠h = 75° because ∠h and the 105° angle are supplementary angles

∠f = ∠h = 75° because ∠f and ∠h are vertically opposite angles

∠c = 105° because ∠c and the 105° are corresponding angles

∠b = 75° because ∠b and ∠f are corresponding angles

∠a = 105° because ∠a and ∠e are corresponding angles

∠d = 75° because ∠d and ∠h are corresponding angles

Step-by-step explanation:

The given diagram includes two parallel lines having a common transversal that crosses both (parallel) lines

By sing angle properties, we have;

∠e = 105° because ∠e and the 105° angle are vertically opposite angles formed by the same two straight lines and are therefore always equal

∠h = 180° - 105° = 75° because ∠h and the 105° angle are angles that form a straight line and are therefore supplementary angles which are angles that sum up to 180°. Therefore, ∠h + 105° = 180°, therefore ∠h = 75°

∠f = ∠h = 75° because ∠f and ∠h are vertically opposite angles

∠c = 105° because ∠c and the 105° are corresponding angles and corresponding angles are equal

Similarly, we have;

∠b = ∠f = 75° because ∠b and ∠f are corresponding angles

∠a = ∠e = 105° because ∠a and ∠e are corresponding angles

∠d = ∠h = 75° because ∠d and ∠h are corresponding angles

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3 years ago

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seropon [69]

If you have 3 1/2 cups of something and you want to find how many 1/4 cups there are the you just need to divide 3 1/2 by 1/4
$3 \frac{1}{2} ÷ \frac{1}{4}$
the answer is 14, there are 14 1/4 cups in 3 1/2 cups.
hope I helped :)

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3 years ago

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nikdorinn [45]

If we make s = Senior tickets,

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to find the values of c and s,w

If we express s in terms of c on t

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