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3 years ago

What is 3x-y=9 2x-y=7

Mathematics

2 answers:

lana [24]3 years ago

7 0

The answer is x: 2 y: -3 and i got it from photomath

svet-max [94.6K]3 years ago

5 0

Answer:

x=2 and y= -3

Step-by-step explanation:

This is a simultaneous equation. To solve this type of equation, there are three methods; substitution, Elimination and Graphical.

But here, we would be using the substitution method.

3x-y=9 Equation 1

2x-y=7. Equation 2

Getting y from equation 2, we have

-y= 7-2x

Multiply both sides by -

y= 2x-7 Equation 3

Substituting y for 2x-7 in equation 1, we have

3x- (2x-7)=9

3x-2x+7=9

x+7=9

x=9-7

x=2

Substituting x as 2 in equation 3

y=2x-7

y= 2(2)-7

y= 4-7

y= -3

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Point M is the midpoint of AB. The coordinates of point A are (−7, 1) and the coordinates of M are (−2, 2). What are the coordin

notka56 [123]

Answer:

$\huge{\boxed{\sf{ ( 3 , 3 ) }}}$

Step-by-step explanation:

Co-ordinates of point A = ( -7 , 1 )

Co-ordinates of point M = ( -2 , 2 )

Let the co-ordinates of point B be ( x , y )

A ( -7 , 1 ) $\longrightarrow$ ( x1 , y1 )

B ( x , y ) $\longrightarrow$ ( x2 , y2 )

Now,

Midpoint = $(\frac{x1 + x2}{2} , \frac{y1 + y2}{2} )$

⇒ $( -2 , 2 ) = ( \frac{-7 + x}{2} , \frac{1 + y}{2} )$

Finding the value of x :

⇒ $-2 = \frac{-7 + x}{2}$

Do cross multiplication

⇒ $-4 = -7 + x$

⇒ $-7 + x = -4$

⇒ $x = -4 + 7$

⇒ $x = 3$

Now, finding the value of y

⇒ $2 = \frac{1+y}{2}$

Do cross multiplication

⇒ $4 = 1+y$

⇒ $1+y = 4$

⇒ $y = 4 - 1$

⇒ $y = 3$

Hence, The co-ordinates of point B = ( 3 , 3 )

Hope I helped!

Best regards!

~ $\text{ TheAnimeGirl}$

4 0

3 years ago

I will mark you brainliest and give 50 points if u help and pls I want the answer to both a and b if u give random answers witho

shusha [124]

Answer:

5a. 4w+24≤100

5b. Dimensions=31ft x 19 ft

Area = 589ft²

Step-by-step explanation:

l=w+12

p=2l+2w

p=2(w+12)+2w

p=2w+24+2w

p=4w+24

The farmer has 100ft of fencing, so maximum that the perimeter (p) can be is 100, meaning (4w+24) has to be less than or equal to 100:

4w+24≤100

For the largest possible perimeter, all 100 of fencing will be used, so allow 100 to be equal to 4w+24)

100=4w+24

4w=76

w=19ft

l=w+12

l=19+12

l=31ft

The dimensions are 31ft x 19ft.

Area=lw

=31*19

=589ft²

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