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3 years ago

Systems of equations, solve by substitution please! x + 7y = -37 4x - 3y = 7

Mathematics

2 answers:

Ann [662]3 years ago

7 0

Step-by-step explanation:

make the coefficients same

then if sign are same subtract the one you wanna cancel it then here it goes

lam gonna start making coefficient of x sam like this:

4.X+7y= -37

1.4X-3y=7

then i will subtract all x or cancel to each other then

4X+28y= -148

4X-3y=7

and then -×-=+

add all y

31y=141

y= 4.55 then we take one of the equation then substitute y to 4.55 so i chose first equation

X+7(4.55)=-37

X+31.85=-37

so take 31.85 to the side it will become -31.85

then X=-37-31.85

X=68.85

i hope that it will help you

Svetradugi [14.3K]3 years ago

5 0

Answer:

1. x = -37 - 7y

2. x = 7+3y/4

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Answer:

The length of the line segment UV is 76 units

Step-by-step explanation:

In a triangle, the line segment joining the mid-points of two sides is parallel to the third side and equal to half its length

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∵ U is the mid-point of ON

∵ V is the mid-point of TN

→ That means UV is joining the mid-points of two sides

∴ UV // OT

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∴ 7x - 8 = $\frac{1}{2}$ (12x + 8)

→ Multiply the bracket by $\frac{1}{2}$

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∴ 7x - 8 = 6x + 4

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→ Subtract 6x from both sides

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∴ x = 12

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3 years ago

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Savatey [412]

Answer:

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Step-by-step explanation:

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3 years ago

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Answer with explanation:

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f'(x)= - 2 x + 8

Put,f'(x)=0

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2 x=8

Dividing both sides by , 2, we get

x=4

Double differentiating the function

f"(x)= -2, which is negative.

Showing that function attains maximum at ,x=4.

Now,f(4)=-4²+ 8× 4-15

= -16 +32 -15

= -31 +32

→→→Function 2:

f(x) = −x² + 2 x − 3

Differentiating once , to obtain Maximum or minimum of the function

f'(x)= -2 x +2

Put,f'(x)=0

-2 x +2=0

2 x=2

Dividing both sides by , 2, we get

x=1

Double differentiating the function,gives

f"(x)= -2 ,which is negative.

Showing that function attains maximum at ,x=1.

f(1)= -1²+2 ×1 -3

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6 0

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