solve the simultaneous linear equations by using the elimination method​

a - b = -3
3a - 4b = -5

Answer:

The value of x so f (x) = 7 is 5.

Step-by-step explanation:

Answer:

x = 79

y = 12

Step-by-step explanation:

x + y = 91

x - y = 67

=> x = (91 + 67) : 2 = 79

=> y = (91 - 67) : 2 = 12

P/s: I don't know how to explain what I just did actually, since we learn how to solve this kind of problem in primary at my place already so it's like a blurry memory about how I learn it. If the math problem is to find 2 numbers, knowing their sum and the difference already, this is how to solve it:

=> Larger number: (Sum + difference) : 2

=> Smaller number: (Sum - difference) : 2

If you can memorize it, good for you! If not then it's alright, this is just a nice tips from me to you. You'll have more advantages in solving these kind of math problem if you can memorized these 2 formulas.

Answer:

-145/63

Step-by-step explanation:

Answer:

1. -20

2. 27

3. 36

4. -200

A) In order to prove that these triangles are congruent by SAS, we need to have two sides of one triangle congruent to two sides of another triangle and an angle of one triangle (that’s included between the sides) is congruent to an angle of another triangle, the triangles are congruent.

We know that side OU is congruent to itself based on the reflexive property and we have a pair of right angles. However, we don’t know that sides MU is congruent to sides NU which would be our final step to prove these triangles are congruent by SAS.

So we are missing that sides MU and NU are congruent.

For part b, we have a pair of vertical angles which means they are congruent and <F and <S are congruent. For ASA, we need two angles and the included side of one triangle congruent to two angles and the included side of a second triangle.

We are not told that PQ and SQ have the same length, so this would be the information we would need to say these triangles are congruent by ASA.

Answer:

1) 44.83 feet 2) 2352.3

Step-by-step explanation:

Answer:

x=15º

Step-by-step explanation:

A triangle's angles add up to 180º.

∠A=30º

∠C=180º-45º

∠B=xº

To find ∠B we have to first find ∠C.

Since ∠C does not have an angle, knowing that a straight line is 180º we can subtract it from 45º to find ∠C.

180-45=135

∠C=135º

Now add ∠A and ∠C.

30+135=165

Subtract the sum from 180º

180-165=x

x=15º

Hope this helps :)

Answer:

  Q = (-2.5, -3), quadrant 3

Step-by-step explanation:

Reflection across the x-axis changes the sign of the y-coordinate.

  Q = (-2.5, -3)

With two negative coordinates, point Q is in Quadrant III.

_____

Additional comment

Point P has a negative x-coordinate and a positive y-coordinate, so is located northwest of the origin in Quadrant II. The quadrant that is southwest of the origin is Quadrant III, which is where points in Quadrant II are reflected to when they are reflected across the x-axis.

Answer:

At 0 hours, there are 100 grams of the substance remaining.

Step-by-step explanation:

Answer:

c

Step-by-step explanation:

I just did it on ed

Decimals can be written in fraction form. To convert a decimal to a fraction, place the decimal number over its place value. For example, in 0.6, the six is in the tenths place, so we place 6 over 10 to create the equivalent fraction, 6/10. If needed, simplify the fraction.

Answer:

50

Step-by-step explanation:

Answer:

50%

Step-by-step explanation:

2/4 = 1/2

1/2 = 0.5

0.5 = 50%

(Could explain slightly more but this should get the point across!)

The slope of the handicap ramp is 1/2

The slope of the handicap ramp is gotten from the equation for the slope of a line, m with endpoints (x₁, y₁) and (x₂, y₂).

m = (y₂ - y₁)/(x₂ - x₁)

Since one point of the ramp can be identified by the ordered pair (d, 4d) and another point on the ramp is identified by the ordered pair (3d, 5d), we have that (x₁, y₁) = (d, 4d) and (x₂, y₂) = (3d, 5d).

Substituting the values of the variables into the equation, we have

m = (y₂ - y₁)/(x₂ - x₁)

m = (5d - 4d)/(3d - d)

m = d/2d

m = 1/2

So, the slope of the handicap ramp is 1/2

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Answers:

========================================

Explanation:

If x repeats itself, then we don't have a function. For instance, relation 2 has the x value -4 show up twice. That input leads to multiple outputs which is why we don't have a function. Relation 4 is a similar story (this time the input 'u' shows up twice).

Relations 1 and 3 don't have this issue, so they are functions.

The solution to the given equation is x = [tex]305\frac{11}{45}[/tex].

The given equation is 45(x-310)=-214.

The solution of an equation is the set of all values that, when substituted for unknowns, make an equation true.

By using distributive property, we get

45x-13950= -214

45x=-214+13950

45x=13736

x=13736/45

x=[tex]305\frac{11}{45}[/tex]

Therefore, the solution to the given equation is x = [tex]305\frac{11}{45}[/tex].

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Jill will have taken 21 in 65 days because 65 divided by 3 is 21.6666666667.

Joe will have taken 16 in 65 days because 65 divided by 4 is 16.25.

Answer:

x=9

y=4

Step-by-step explanation:

Answer:

The given equation is true for all x.

Step-by-step explanation:

Answer:

x=5

Step-by-step explanation:

I took the test. Hope this helps

The solution of the given equation is when the x = 5.

An equation is an expression that shows the relationship between two or more numbers and variables.

Given that the equation 1/4x−3/4=1/2, also the replacement set {−1, 1, 5}

First, substitute the values from the given set;

When x = -1

1/4x−3/4=1/2

1/4(-1) − 3/4 = 1/2

-1/4 - 3/4 = 1/2

-4/4 = 1/2

-1= 1/2

This is not the solution to the given equation.

When x = 1

1/4x−3/4=1/2

1/4(1) − 3/4 = 1/2

1/4 - 3/4 = 1/2

-2/4 = 1/2

-1/2 = 1/2

This is not the solution to the given equation.

When x = 5

1/4x−3/4=1/2

1/4(5) − 3/4 = 1/2

5/4 - 3/4 = 1/2

2/4 = 1/2

1/2 = 1/2

This is the solution to the given equation.

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Answer:

It should be A & D

Step-by-step explanation:

These two are the only ones that have the exact same numbers on all three sides. They are congruent based on SSS.

we have 67/x . 100% = 0.12 %

so x = 67.100%/0.12% = 55833,(3) ≈ 56

ok done . Thank to me :>

Answer:

If a shirt is on sale for 50% off, and you have another offer that gives you an "additional 20% off the sale price", does that mean you get a total of 70% off? Not usually. If the shirt was $20, then the SALE price would be $10 and the additional 20% would apply to the SALE price of $10 instead of the original price of $20. This isn't too bad when the sales are nice even percentages, but when it gets more complicated, you can use this calculator to find out the final cost (sales tax not included).Step-by-step explanation:

Step-by-step explanation:

is it really v2x?? or smthg else

Answer:

16

Step-by-step explanation:

Because 25 - 9 = 16

The residual column is given by the difference between the given values

and the values from the fitted line.

Reasons:

The line of best fit equation is; y = 2.55·x - 3.15

The 4-column table is presented s follows;

[tex]\begin{tabular}{|c|c|c|c|}\underline{x}&\underline{Given}&\underline{Predicted}&\underline{Residual}\\1&-0.7&-0.6&-0.1\\2&2.3&1.95&0.35\\3&4.1&4.5&a\\4&7.2&7.02&b\end{array}\right][/tex]

Required:

The values of a and b

Solution;

The residual is given by the difference between actually observed value and the predicted value

RESID = [tex]\mathbf{y_i}[/tex] - [tex]\mathbf{x_i}[/tex]·b

Where;

[tex]y_i[/tex] = The given value at point i

[tex]x_i[/tex]·b = The predicted value at point i

Therefore;

At x = 1, the residual = -0.7 - (-0.6) = -0.1

At x = 2, the residual = 2.3 - 1.95 = 0.35

At x = 3, the residual = a = 4.1 - 4.5 = -0.4

Therefore;

At x = 4, the residual = b = 7.2 - 7.02 = 0.18

Therefore;

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Answer:

33 cars please give Brainliest

P(A n B) = P(A U B) - P(A) - P(B)

= 11/12 - 3/4 - 1/2

= (11 - 9 - 6)/12

= 4/12

= ⅓

Answer:

a. n=6

b. n = 4

c. n =2

d. n = 11 ÷ 5

e. n = 10

f. 20

Step-by-step explanation:

a. 5n = 30

n=30÷5

n=6

b. 3n-1 = 11

3n= 11 + 1

n = 12 ÷3

n=4

c. 4n + 7 = 15

4n = 15 - 7

n = 8 ÷ 4

n = 2

d. 5n = 11

n = 11 ÷ 5

e. 4 + n = 40

n = 40 - 4

n = 10

f. 5 + 15 = 20